Read Chapter 3 text version


Written in cooperation with Oregon State University, Department of Public Health, Environmental Health and Occupational Safety Management Program


1.1 Purpose and Use of the Staton Companies Safety Manual 1.2 Worker Motivation: Safety is Everyone's Responsibility

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2.1 Engineering Survey 2.2 Utility Location 2.3 Medical Services and First Aid 2.4 Fire Prevention and Protection


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3.1 Signs and Lighting 3.2 Safe Use of Ladders 3.3 Safe Use of Scaffolding 3.4 Aerial Lifts 3.5 Shoring 3.5.1 Vertical Shoring 3.5.2 Lateral Shoring


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4.1 Safe Work Clothing 4.1.1 Temperature Stresses 4.2 Hand Protection 4.3 Foot Protection 4.4 Head Protection 4.5 Eye and Face Protection 4.6 Hearing Protection 4.7 Respiratory Protection 4.8 Fall Prevention and Protection 4.8.1 Personal Fall Arrest System 4.8.2 Guarding of Roof Perimeters


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DEBRIS REMOVAL 5.1 Selective Demolition

5.1.1 Floor Openings 5.2 Complete Demolition

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6.1 Inspection of Equipment 6.2 Heavy Equipment Maintenance 6.3 Machinery for Transport 6.3.1 Loading 6.3.2 Securing 6.4 Safe Use of Material Handling Equipment 6.4.1 Loaders 6.4.2 Basements 6.4.3 Stockpiling Debris 6.4.4 Attachments 6.5 Safe Use of Trucks 6.5.1 Loading 6.5.2 Hauling 6.5.3 Dumping 6.6 Safe Use of Cranes 6.6.1 Load Charts 6.6.2 Crane Features 6.6.3 Hydraulics 6.6.4 Machine Assembly and Set-Up 6.6.5 Use of a Signalman 6.6.6 Operator Safety Responsibilities 6.6.7 Demolition Ball 6.6.8 Clamshell Bucket 6.6.9 Electrical Hazards

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7.1 Safe Handling of Asbestos 7.1.1 Health Effects of Exposure to Asbestos 7.1.2 Applicable Government Regulations 7.1.3 Planning 7.1.4 Preventing Fibers from Becoming Airborne 7.1.5 Protective Practices for Workers 7.1.6 Disposal of Asbestos 7.2 Safe Handling of PCBs 7.2.1 Health Effects of Exposure to PCBs 7.2.2 Applicable Government Regulations 7.2.3 Planning 7.2.4 Preventing Occupational Exposure 7.2.5 Protective Practices for Workers 7.3 Avoiding Overexposure to Lead 7.3.1 Uses of Lead 7.3.2 Potential Health Effects of Exposure to Lead 7.3.3 Applicable Government Regulations 7.3.4 Planning 7.3.5 OSHA Exposure Limits 7.3.6 Exposure Monitoring and Assessment 7.3.7 Methods of Compliance 7.3.8 Protective Practices for Workers


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Chapter Title 8 WELDING (Torch Cutting)

8.1 Safe Use of Cutting Torches

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9.1 General Hand Tool Safety 9.2 Hand Tool Safety Strategies 9.3 Hand Tools 9.4 Power Tools 9.4.1 Electric Power Tools 9.4.2 Pneumatic Power Tools 9.4.3 Gasoline Power Tools 9.4.4 Abrasive Blade Tools 9.4.5 Chainsaws 9.4.6 Air Compressors


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10.1 Fire Precautions 10.2 Use of Explosives 10.3 Non-Explosive Demolition Agents


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11.1 Safety When Working in Confined Spaces 11.1.1 General Safety Hazards 11.1.2 Safe Work Practices 11.2 Safe Practice When Demolishing a Chimney or Stack 11.2.1 Safe Work Practice 11.2.2 Debris Clearance 11.2.3 Worker Safety 11.2.4 Demolition by Deliberate Collapse 11.3 Demolition of Pre-Stressed Concrete Structures 11.3.1 Recognizing Pre-Stressed Concrete Structures 11.3.2 Categories of Pre-Stressed Concrete 11.3.3 Hazards of Pre-Stressed Concrete 11.3.4 Recommended Procedures for Demolition 11.3.5 Job Site Safety 11.3.6 Basic Definitions and Principles


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Chapter 1 The importance of Safety


Importance of Safety

1.1 Purpose and Use of the Staton Companies Safety Manual This safety manual was prepared jointly by Staton Companies and Oregon State University department of Public Health, Environmental Health and Occupational Safety Management program. This manual has two purposes. These are to catalogue in one volume, safe ways to perform diverse tasks when demolishing structures and to establish industry safe work practices for Staton employees. This Safety Manual will catalogue safe methods for performing the various tasks involved in demolition. The methods are based upon the National Demolition Associations recommendations, and OSHA, EPA and other agency regulations. It is designed to be used in planning activities, as a quick reference, and as a training guide for industry safe work practices for demolition and related activities. It should be noted that no Safety Manual can take the place of common sense, handson trainings, and years of experience in eliminating occupational safety issues. 1.2 Worker Motivation: Safety is Everyone's Responsibility Staton Companies is committed to worker safety. Staton Companies takes a proactive approach to safety education and training in order to ensure worker safety. However, individual employees also have responsibility for job safety at Staton. Workers are expected to be active participants in the safety process by: Reading and understanding Staton written health and safety policies Abiding by all safety rules Participating in planning for safety at job sites Informing a site supervisor of any possible hazards Actively participating in safety briefings Actively participating in safety trainings and education Modeling safe practices for less experienced workers and non-Staton employees

All employees must know that the company will not tolerate unsafe workers and unsafe work practices. Staton Companies is serious about safety and will enforce the policies of the safety program. Staton Companies believes that safety incidents are preventable when policies, training and common sense are adhered to.




Preparatory Operations

Before the start of every demolition job, Staton Companies will take a number of steps to safeguard the health and safety of workers at the job site. These preparatory steps involve the overall planning of the demolition job, including the means and equipment necessary to do the job. Staton Companies believes the planning for a job is as important as performing the work, especially in regard to the safety and health of Staton employees and the community. 2.1 Engineering Survey (29 CRF 1926.850 (a)) OSHA regulations require an engineering survey of the structure, conducted by a properly qualified person, prior to the start of demolition. A copy of this survey should be kept at the Staton office and at the job site. The purpose of this survey is to identify any hazards and determine the condition of the structure. Any existing damage to neighboring structures should also be documented. The engineering survey provides the opportunity to evaluate the job in its entirety. The engineering survey should contain the following elements: A plan for the demolition of the structure(s) The equipment to be used to do the work Safety measures for Staton employees A written determination that the structure is safe to demolish using the above plan

During the preparation of the engineering survey, planning for potential hazards and emergencies should be addressed. If the structure to be demolished has been damaged by fire, flood, explosion or some other cause, appropriate measures should be taken. This may include bracing and shoring of walls, floors and/or adjacent structures. The engineering survey should list all types of hazardous chemicals, gasses, explosives, flammable materials, or similar dangerous substances that may have been used or stored on the site. If the nature of a substance cannot be easily determined, samples should be taken and analyzed by a qualified laboratory prior to demolition. Care must always be taken when addressing any suspect material. Do not rely solely on labels. As part of OSHAs Hazard Communication Standard, Material Safety Data Sheets (MSDS) are required from the client, covering all materials that could be encountered at a job site. All necessary training and protection for anticipated hazards must be provided. Information about materials should be obtained from the structures owner when possible or from an investigation of the structures records.


However, even when there has been full disclosure and a thorough search of a structures records, it is still possible workers may encounter unknown, possibly harmful substances. It is the responsibility of every Staton employee to notify a site supervisor immediately upon finding an unknown material. Workers must also be especially careful when working around deteriorating or damaged pipes, drums or tanks. Workers must notify a site supervisor immediately of any leaks or spills. During the planning stage of a job, all safety equipment needs should be determined. The required number and type of respirators, life-lines, warning signs, safety nets, special face and eye protection, hearing protection, and other personal protective equipment should be determined during the engineering survey. However, it is understood that demolition is dynamic in nature and changes may have to be made as new information is obtained in the course of the job. It is important to document any changes to the engineering survey as new information is obtained. Please note that a comprehensive plan is necessary for any confined space entry. Please see Section 12.1 for more information regarding confined space entry. 2.2 Utility Location (CFR 1926.850 (c), (d))

One of the most important elements of pre-job planning is the location of utility services. All electric, gas, water, steam, sewer, and other service lines should be cut off, capped, or otherwise controlled at or outside the building before demolition work is started. In each case, any utility company that is involved should be notified in advance, and its approval for services, if necessary, should be obtained. If it is necessary to maintain any power, water or other utilities during demolition, such lines should be temporarily relocated as necessary or protected. The location of all overhead power sources should be determined, since they can be especially hazardous during machine demolition. All workers should be informed and take notice of the location of any existing or relocated power service.


2.3 Medical Services and First Aid (29 CFR 1926.23)

Demolition can be a hazardous business. Working in a deteriorated structure at a congested job site can also increase the potential for injury. Proper planning can minimize the hazards at the job site and aid in responding if an incident does occur. Prior to starting work, the site supervisor must make provisions for prompt medical attention in case of serious injury. The location of the nearest hospital, infirmary, clinic or physician must be posted at the job site. The site supervisor must know the most direct and accessible routes to local medical facilities. In addition, the job site must be equipped with an appropriate communication system such as a cell phone in order to contact any needed ambulance service. Every effort should be taken to ensure that Staton employees have current CPR and First Aid certifications. A properly stocked First Aid kit must be available at all Staton job sites. This kit should contain appropriate supplies in a weatherproof container with individually sealed packages for each type of item. It should also include rubber gloves to prevent transfer of infectious diseases. Provisions must be provided for the quick flushing of eyes. The contents of the kit should be checked periodically and documented. Any used supplies should be immediately replaced. 2.4 Fire Prevention and Protection (29 CFR 1926.25, 1926.150-1926.155, 1926.352)

The potential for serious fires at demolition sites is great because of the accumulation of materials and debris, as well as the presence of possible sources of ignition. A fire protection plan should be implemented with the designated fire fighting plan at each job site. Staton employees must each know what his/her role is in the case of fire. In addition, evacuation plans for job sites and Staton offices are to be posted. It is each employees responsibility to know the evacuation plan at a job site.


Common sense should be the general rule in all fire protection and prevention. All potential sources of ignition should be evaluated and the necessary corrective measures taken. Each Staton employee must report anything concerning that could lead to a fire. Some fire prevention and protection issues to be aware of are the following: Any fire fighting equipment at the Staton offices or at a Staton job site needs to be maintained at all times and periodically inspected with documentation. Defective equipment must be replaced immediately. Electrical wiring and equipment for providing light, heat or power must be installed by a competent person and inspected regularly. Equipment powered by an internal combustion engine must be located so that the exhaust discharges are well away from combustible materials and workers. Internal combustion equipment must be shut down prior to refueling. Smoking is prohibited near hazardous operations or materials. Free access to fire hydrants and to outside connections for water must be maintained at all times. Lastly, the fire department must be called for all fires. Fire fighting is extremely dangerous and must be handled by professionals. Workers must only provide fire protection for which they have been trained. Workers are discouraged from taking unreasonable fire fighting risks.


Chapter 3 Protective Structures


Protective Structures

A variety of protective structures are used to protect demolition workers, as well as the public, from the hazards at a demolition site. Ladders, scaffolds, and powered manlifts, when used properly, provide easy and safe access to high places. Guard rails and roof guards enable workers to work safely on sloping roofs. Sidewalk canopies, temporary walkways, catch platforms, and fences protect the public from demolition activities. Shoring is a means of retaining structures that are unstable or may become unstable during demolition. 3.1 Signs and Lighting (29 CFR 1926.26, 1926.56, 1926.200)

Signs and lighting may be used to point out hazards at a work site. To announce every hazard on the job site with a sign would be impossible. However, awareness of those hazards which are unexpected by the worker or the public can be achieved by the appropriate use of signs. Standardized signs, which are more easily recognized than others, should be used. Signs bring attention to similar situations should have similar designs. This includes signs describing various electrical, chemical or explosive hazards. Accident prevention tags are used as temporary warning indicators. They are used when a temporary condition presents a hazard such as a machine under repair or until a permanent sign can be installed. The following signs should be used only in the specific circumstance described: DANGER signs shall be used only where an immediate hazard exists. CAUTION signs are used to warn against potential hazards or to discourage unsafe practices. EXIT signs are used to indicate which doors and passageways lead to safety.


DO NOT OPERATE tags are used on equipment under repair. Sufficient lighting is vital to safe working conditions. While natural light may be sufficient for some work, light levels during early morning and late afternoon, as well as insufficient light due to bad weather, nearby structures, or dust, can easily result in unsafe light levels. Artificial lighting should be utilized if there is any question about the ability of workers to work safely under natural light condition. It is essential that lighting is adequate in all walkways and corridors leading to work areas. OSHA requires that construction areas, ramps, runways, corridors, offices, shops and storage areas shall be lighted to not less than the minimum illumination intensities while any work is in progress. The following table should be used as a guideline: Footcandle 5 3 5 5 10 Areas of Operation General construction area lighting General construction areas, concrete placement, excavation and waste areas, loading platforms, refueling, and field maintenance areas Indoors: warehouses, corridors, hallways, and exitways Tunnels, shafts, and general underground work areas General construction plant and shops (e.g., mechanical and electrical equipment rooms, carpenter shops, rigging lofts, active storerooms, locker or dressing rooms, indoor toilets and workrooms) First aid stations, infirmaries and offices


3.2 Safe Use of Ladders (29 CFR 1926.1050, 1926.1051, 1926.1053, 1926.1060)

Ladders are used extensively in demolition and are classified as either fixed or portable. Fixed ladders are considered to be permanent fixtures of a structure, whereas portable ladders may be moved. Portable ladders include stepladders, straight ladders, and extension ladders and can be manufactured of fiberglass or wood. Straight ladders may be single rung or double rung. The following are safety measures to keep in mind while using ladders:


If simultaneous two-way traffic is expected on a ladder, or if a ladder is to provide the only means of entering or leaving a working area for 25 or more employees, a double rung ladder is required. Each ladder must be the proper size and strength of construction for its intended use. All ladders must be free from cracks, splits and other deformities that might reduce their ability to withstand stress. An inspection should be performed by the worker before using the ladder. Workers should also inspect their own shoes and the ladder rungs for oil, grease and debris for ladder use. Ladders must be secured to the platforms and extend at least 36 inches above the higher platform, roof or other surface. Landing platforms cannot be less than 2 feet wide and 2 ½ feet long. Never tie or splice two ladders together in order to extend their length. Never use ladders as platforms, runways or scaffolds. Ladders should be made of wood or fiberglass and be type 1-A. Ladders should not be painted as this can hide defects. Clear varnish can be used if hand protection is needed. The use of metal ladders is prohibited as they are not as strong as wood and fiberglass, are conductors of electricity, and can slide on smooth surfaces. The ideal angle for ladders to be set against a structure is 75 degrees or 1 foot horizontally away from the structure for every 4 feet of vertical rise. Angles less than 75 degrees are not built to withstand lateral stress and should be avoided. If a ladder must be placed in a doorway or passageway, guards or barricades must protect it. Tools and heavy or bulky materials should never be carried up or down a ladder, or hung on a ladder. The potential for an accident exists whenever a worker is on a ladder. Before each use, all ladders should be inspected for splits, cracks and defective rungs. Any defects must be reported to a Staton site supervisor or the person in charge. The defect must be immediately repaired, tagged for non-use or destroyed. The primary causes of ladder-related accidents are failure to face the ladder at all times, overreaching on either side, and pushing/pulling an object sideways to the ladder. It is expected that Staton employees will not engage in these dangerous activities. A good rule to keep in mind is to keep your belt-buckle inside the side rails.

3.3 Safe Use of Scaffolding (29 CFR 1926.450-1926.452, 1926.454)


There are several different types of scaffolds. Staton only uses built-up scaffolds. If an employee has not had experience with built-up scaffolds, it is his/her responsibility to request orientation to this type of scaffolding. There are general safety rules that should always be followed when using scaffolding. 1. Check the materials before erecting the scaffold to ensure all are in good condition. Check to make sure all wood materials are intact and that no steel materials are rusted, bent or warped. 2. The building of the scaffold should only be done by workers who have demonstrated to a site supervisor that they are competent to do so. 3. The site supervisor will supervise the building of the scaffold. 4. The site supervisor will inspect the scaffold before any workers use it. 5. The soil where the scaffold is built must be inspected to ensure it can bear the weight of the scaffold. If there are concerns that the soil cannot withstand the weight of the scaffold, these must be reported to the site supervisor immediately. 6. A designated worker or the site supervisor will periodically inspect the scaffold to ensure there are no hazards. This includes ensuring the scaffold area is kept free of litter, debris, grease, oil or other hazards. Sensible safety precautions must be observed when working on scaffolds. Proximity to live electric power lines must be avoided. Platforms should be kept clear of possible tripping hazards. If ice or snow is present, it should be cleared from the platform and sand or other non-skid materials applied to the surface. Damaged sections must be removed and repaired before further use. 3.4 Aerial Lifts (29 CFR 1926.453, 1926.454) Workers are expected to be trained in the proper care and use of aerial lifts. Personnel on the ground are expected to know how to lower the basket from ground controls in case of an emergency. A pre-use inspection must be performed on each aerial lift. Copies of inspection documents will be kept on-site. Aerial lifts should be used only on smooth, firm, level surfaces and away from any traffic. When traveling, the basket should be lowered as close to the ground as possible.


All occupants must wear harnesses, along with shock absorbing lanyards. These safety harnesses must be tied off to the brackets provided in the aerial lift, not the units hand rail. 3.5 Shoring (29 CFR 1926.1050) Maintaining the structural integrity of the building under demolition and any nearby structures is critical during the demolition process. The stresses created during the removal of walls and supporting members, the loads imposed by mechanical equipment and falling or stored debris must be taken into account. In the event that the structural integrity of the building does not provide a sufficient factor of safety for these loads, shoring should be implemented. Shoring devices can provide either vertical (such as holding up a floor) or horizontal (such as a retaining wall) support. The equipment used for shoring can be either wood or steel. It should be inspected prior to each use. Steel should be checked for rust, bends, and cracked welds. Wood should be checked for splitting, warping and cracking. The stability of the shoring device, as well as the structure it is retaining or supporting, must be inspected on a regular basis during the course of the project. 3.5.1 Vertical Shoring Vertical shoring may be required when walls or columns are removed or when the weight of mechanical equipment or debris exceeds the safe loading capacity of a floor. Particular attention must be paid to the impact loading of falling debris, which is considerably greater than the load imposed by the debris at rest. Timbers, steel posts or shoring towers may be used in order to accomplish vertical shoring. Adjustable screw jacks, threaded collars, or wedges are used to secure the shoring in position. Individual posts must not be stacked or tiered to reach higher ceilings. At Staton the site supervisor or other manager will determine the placement of shoring. A location should be selected with solid footing. Shoring should be placed on base plates which are positioned on the footing, and the shorehead should be centered on the beam overhead. Baseplates and shoreheads distribute the load over a wider area. Before tightening, the shoring must be plumbed to provide maximum stability. If a wedge is used for tightening, the plumb should be checked afterward. 3.5.2 Lateral Shoring There are several instances where lateral shoring may be required. When a building that has a ,,party (shared) wall with another building is demolished, the remaining building may need to be temporarily shored. Foundation walls which serve as retaining walls to support earth or adjoining structures should not be demolished until proper bracing is in place.


Free-standing wall sections that are more than one story must have lateral bracing, unless the wall was originally designed and constructed to be self-supporting and stand higher than one store without lateral support. Walls must be left in a stable condition at the end of each shift. Shoring may be required after the removal of interior floors due to the potential shift in lateral stresses.


Chapter 4 Personal protective equipment


Personal Protective Equipment

A number of hazards in demolition work require the use of personal protective equipment (PPE). These hazards range from sharp edges on debris to exposure to hazardous chemicals. PPE is designed and work to protect the worker from these hazards. Protective equipment includes safety glasses, face shields, hard hats, safety shoes, respiratory devices, personal fall arrest systems, and proper clothing. Staton is committed to worker safety and will ensure that each worker has the right equipment for the right job. Staton site supervisors and other managers will determine what PPE should be used at each job. The site supervisor and other managers will also enforce the specific PPE requirement of each job site. Due to the dynamic nature of demolition, each job site is different in what hazards may be present. It is each workers responsibility to notify a site supervisor or other manager if he or she discovers a hazard at a job site which was previously unknown. Staton operates under a 100% policy which means that if a certain type of PPE is required for a certain job, then every person in that area (including supervisors and visitors) must where the appropriate PPE. 4.1 Safe Work Clothing It is each employees responsibility to report for work each day in appropriate, safe work clothing. At Staton, we recommend clothing that fits properly as loose-fitting clothing can get caught in machine parts or on protruding objects. Long-sleeved shirts are highly recommended to protect arms. Pants are required, as well as appropriate footwear. It is also recommended that jewelry not be worn to demolition sites. Jewelry is dangerous near electrical equipment, machinery, jagged edges and protruding objects. 4.1.1 Temperature Stresses

Heat, cold, and rain place stress on the body. These effects can be compounded by heavy work. The combined effect of these stresses can lead to life-threatening situations, such as development of hypothermia (loss of body heat), heat exhaustion, and heat stroke. Though the climate at most jobs in the Northwest is usually mild, there can be work days which involve extreme weather conditions. Site supervisors at Staton are expected to watch for any hazards associated with weather and make appropriate decisions for worker safety. In addition, workers must be aware of their own response to extreme weather conditions and notify their supervisor if weather conditions are causing undue stress, injury or illness to themselves or a co-worker.


4.2 Hand Protection

In most cases, general duty gloves made from leather, cotton, and/or fabrics provide adequate protection against hand injuries in demolition work. They allow considerable dexterity while shielding the hands from minor cuts, splinters, abrasions, and dirt. Wearing gloves while operating equipment that requires tactile feedback to the hands (excavators) is not recommended. For work in wet areas, rubber or vinyl gloves may be recommended. Insulated gloves and work glove liners are available for cold weather work. In addition, many types of ,,sleeves are available to protect the workers arms from cuts, scrapes and burns. Site supervisors will advise workers of any specific job site requirements or recommendations for hand protection. In addition, it is each workers responsibility to use common sense when handling dangerous items which could cause injury. 4.3 Foot Protection (29 CFR 1926.96)

Injuries to the foot make up a large percentage of injuries in the demolition injury. For this reason, it is imperative that workers wear adequate footwear on job sites. Leather work shoes (no athletic footwear) are required at all Staton job sites. Each employees work shoes must be in good repair, free from split seams, holes and dragging laces. Staton does not require steel-toed boots. However, there are times when Staton works at a job site where steel-toed boots are required. It is each employees responsibility to wear steel-toed boots to those jobs. A common foot injury in demolition work results from stepping on nails or other hazardous items at work sites. Removable steel insoles and shoes with steel-reinforced insoles are available which minimize this hazard. At the very least, shoes with thick rubber soles must be worn in areas where puncture injuries can be anticipated. Slips and falls are another common cause of injuries that can be reduced by the use of proper footwear. Shoes with adequate treads must be worn in areas where slippery surfaces can be expected. Workers working in wet areas for extended periods of time can use rubber boots over safety shoes. Site supervisors will advise workers when this is needed. 4.4 Head Protection (29 CFR 1926.100)


The use of hard hats is mandatory at all Staton job sites as there is possible danger of head injury from impact, falling or flying objects, burns, or electrical shock. Blows to the head are cushioned by the shock-absorbing nature of the hats suspension because the impact is distributed over a wide area. In addition, hard hats can protect the face and neck from injury. At Staton when workers at a demolition site are operating machinery with a closed cab, a hard hat can be removed when the worker is in the interior of the cab. However, before exiting the machinery cab, the worker is required to put his or her hard hat back on. At Staton a Class A Limited Voltage Protection (standard hat) is the recommended type. Bump-hats, which are close-fitting plastic hats with no suspension, do not provide a sufficient degree of protection for demolition work and are not permitted at Staton job sites. In addition, Class C No Voltage Protection (aluminum hat) are not permitted at Staton, unless specified for a particular job site. A wide variety of accessories for hard hats are available to provide additional protection and comfort. Winter liners are snug-fitting cloth hats that fit under and attach to hard hats. It is important that no hat, other than a liner, be worn under a hard hat. Hard hats can be obtained which have earmuffs, face shields, and welding visors attached directly to the hat. It is important that no attachments interfere with the basic protection a hard hat provides. Workers are not permitted to drill holes in hard hats. These can reduce the structural integrity of the hat. It is each workers responsibility to ensure that his or her hard hat is in good condition with no cracks, dents, or other damage due to impact or wear that might reduce the hats effectiveness. Any hard hat that is cracked, dented or damaged must be replaced. Any hat with defective parts should be removed from service until the parts have been replaced. Periodically, hard hats should be washed with hot soapy water, so that defects or damages can easily be seen. Storage of hard hats in extreme heat or cold can reduce the strength of the shell material. Therefore, hard hats should be stored in temperate conditions. Painting of hats is prohibited because certain chemicals in paint can deteriorate the materials used in the hat construction. 4.5 Eye and Face Protection (29 CFR 1926.102)

The need for eye and face protection changes from moment to moment on the job site. Certain activities demand the use of specific protective devices. In any operation which


may produce flying dust, sparks or sprays, workers must protect their eyes and faces. Job site supervisors will make every effort to determine the needed protection and provide the appropriate PPE. However, demolition work can change quickly and unexpectedly. Therefore, each worker is responsible for reporting any conditions which could potentially injure the eyes and face. Eye and face protective devices consist of safety glasses, goggles, face shields, welding goggles and welding helmets. Safety glasses and goggles are designed to protect the eyes from dust, flying particles, sparks, and splashing liquids. Face shields provide additional protection from the same hazards and should only be worn over safety glasses or goggles. Eye and face protectors must provide adequate protection against the hazards for which they are used. The only protectors which should be used are those which conform to ANSI standards for impact resistance, heat deformation, flammability and durability. Workers must ensure that any glasses, goggles and shields they use are kept clean and in good repair. Lenses and other clear parts must be kept free from fog, pits or scratches. Lens which are badly pitted, scratched or cracked or have lost some of their impact resistance should be replaced. Fogging can be reduced or eliminated by using special fog-proof cleaning compound. Defective support pieces, such as frames, straps or helmets must be replaced. Eye protection should fit snugly and comfortably without interfering with the workers movement or vision.

4.6 Hearing Protection (29 CFR 1926.101)

Day to day exposure to loud noises can result in a permanent loss of hearing. Damage to hearing occurs when a person is exposed to excessive noise levels. Demolition sites can have significant and potentially harmful levels of noise. During these times, some form of PPE should be worn, such as ear muffs, disposable fiber or foam ear plugs or reusable rubber plugs. Cotton provides little protection and should not be used. Workers who use ear protection should wear them according to the manufacturers instructions and recommendations. Workers should be aware that ear protection generally works better if ears are kept clean. In addition, dirt in the ears combined with the use of ear plugs, can lead to infection. In addition, workers must keep in mind while wearing ear protection that their hearing is somewhat reduced, and they may have difficulty hearing other workers, backup alarms, and other important noises. 4.7 Respiratory Protection (29 CFR 1926.103, 1926.134)


The use of respirators is required whenever entering an area in which the concentration of airborne contaminants exceeds permissible exposure limit (PEL) standards. Supplied air breathing devices may also be necessary when workers enter areas deficient in oxygen. Staton makes every effort to avoid exposing workers to hazardous atmospheres whenever possibly with the use of engineering or administrative controls. Engineering controls, such as ventilation and spraying dusty areas with water, can often reduce the level of contaminants to the point where a respirator is no longer needed. Similarly, administrative controls, such as changing work procedures or schedules to eliminate exposures to hazardous atmospheres, should be used whenever possible. 4.8 Fall Prevention and Protection (29 CFR 1926.104, 1926.451 (g), 1926.5001926.503)

Fall prevention is the first step of fall protection. Proper training of workers and engineering controls such as guardrails and floor coverings may be used to prevent a fall whenever possible. Fall protection should be in place when there is a possibility of the fall prevention failing. Several types of fall protection equipment are used to reduce injuries from falls in the demolition industry. Personal Fall Arrest Systems (PFAS), safety nets and catch platforms can all serve to prevent a worker who has started to fall from hitting the ground or other dangerous surfaces. If an individual worker has not been trained on a fall protection system which is being used for a particular job, it is his/her responsibility to tell the site supervisor. Additional training may be necessary. 4.8.1 Personal Fall Arrest System Personal fall arrest systems are designed to protect against falls in a variety of situations. The supporting member that PFAS is attached to is called an anchor point. Vertical lifelines (or droplines) are ropes or cables that hang from one anchor point; horizontal lifelines are stretched between available anchor points and on whether vertical or horizontal mobility is more important to performing the job. Each vertical lifeline must be capable of supporting one worker who is attached to the lifeline. A horizontal lifeline must be designed and installed by a qualified person and have a safety factor of at least 2. A full body harness distributes the shock load over the seat and thighs. A shock absorbing lanyard is a device which connects the harness to the anchor by means of a double locking snap hook. Retractable lanyards are also available. These are retracting lines that automatically engage and catch the line during a fall.


All anchor points, cables and slings used for a PFAS should be capable of supporting a minimum dead weight of 5,000 pounds. All PFAS hardware should be constructed of drop forged or pressed steel capable of withstanding a tensile loading of 5,000 pounds without suffering deformation. Harnesses and lanyards must be secured directly above the worker to prevent them from swinging into structural members or other workers in the event of a fall. The ideal free-fall distance is as close to zero as possible; maximum allowable free fall distance is 6 feet. Minimizing free fall and supporting horizontal lifelines every 50 feet are important in preventing swing injuries. It is also important that the "D" ring is worn between the shoulder blades since the body only bends in one direction at the torso. Full body harnesses should be used whenever the potential for a free fall exists. There are various types of harnesses and lanyards, made from several different materials. It is important to select a PFAS that is appropriate for the demolition work to be performed. All slings, harnesses, ropes and cables should be protected from abrasion, contact with oils and other chemicals, burns, and moisture. Water could allow for material to stretch up to 15%, thus dramatically increasing free fall distance. All fall protection equipment should be inspected on a regular basis. PFAS equipment should be inspected before each use in addition to periodic, formal inspections by a competent person. It is each workers responsibility to notify a site supervisor or other manager if the fall protection equipment appears damaged or comprised in any way. 4.8.2 Guarding of Roof Perimeters Special safety precautions must be taken when workers are working on roofs with a ground-to-eave height greater than 6 feet. These provisions do not apply to workers who are inspecting or surveying roof conditions, nor do they apply at points of access. Workers on steep roofs must be protected from falls. Several options exist for this situation:

Standard guard rails Scaffolds with guard rails Safety nets PFAS

Requirements for protecting workers on low slope roofs are less strict. A system of direct supervision of a system of warning lines may be selected if conditions permit. A warning line is a barrier of high visibility material that is intended not as a restraining device, but rather to alert workers of the proximity of the roof edge. Warning lines should be erected at least 6 feet from the roof edge around all sides of the work area. When mechanical equipment is in use, the warning line should be erected at least 10 feet from the roof edge. Workers using mechanical equipment within 10 feet of the roof


edge must be protected by using a safety-monitoring system. A competent person must be responsible for recognizing and warning workers of fall hazards.


Chapter 5 Debris removal

Debris Removal (29 CFR 1926.252, 1926.852)


5.1 Selective Demolition 5.1.1 Floor Openings (29 CFR 1926.502 (i), 1926.853, 1926.854 (e)) Debris removal operations conducted inside the walls of a structure are usually accomplished through floor openings. When they are available, existing floor openings such as elevator and ventilations shafts should b used for this purpose. Otherwise, a qualified person should be consulted prior to cutting floor openings. Floor openings must not take up more than 25% of the total floor area on each level, unless the lateral supports are left intact. Supporting beams must be left intact wherever possible, but when floors are weakened or otherwise made unsafe, they must be shored to carry the intended load from demolition operations. Pre-cast or post-tensioned concrete floors must never be cut, unless a Professional Engineer is consulted. Each entrance to each level with one or more floor openings should be posted with Warning signs, which indicate the nature of the hazard. During the debris removal, securely fastened bumpers, 4" thick by 6" high must enclose the opening on the uppermost floor from which debris is being dumped. Intermediate floor openings must be barricaded by a substantial guard rail, midrail, and toe board extending 39-45 inches high and located at least 6 feet from the opening. Debris cleaning operations on the bottom floor must not begin until all dumping has stopped. All floor openings which are not in use as material drops, should be covered with a material capable of withstanding any load. Covers must be properly secured to prevent their movement and should be flush with the floor level. Covers shall be labeled and secured as per 29 CRF 1926.502(i). 5.2 Complete Demolition All demolition material will be processed down to manageable sizes. Regulated demolition material will be loaded onto trucks for transportation to an appropriate recycling facility or licensed landfill. Concrete and brick demolition material will be processed down for recycling or disposed of in an approved, legal manner, as fill material. Voids and depressions will be filled or smoothed, where applicable. Site grading will be performed to achieve a uniform grade as shown in the grading plan. Utilities will be capped according to local authorities.


Chapter 6 Equipment safety

Equipment Safety


This section covers the safe use and operation of cranes, bulldozer, excavators, frontend loaders, and trucks. This equipment represents the largest source of potential hazards on demolition sites. The section will review the essential elements of inspecting, maintaining, operating and transporting heavy equipment. The information should be used in conjunction with owners manuals, operator training manuals, ANSI and OSHA standards. There is no substitute, however, for years of training and experience. Therefore, it is essential for newer workers to be encouraged to observe and learn from more experienced workers. 6.1 Inspection of Equipment (29 CFR 1926.550 (a) (5), (6), 1926.601 (b) (14))

An essential element in keeping workers safe in demolition is to ensure that equipment is regularly inspected. Periodic inspections are usually described in equipment owners manuals. These should be consulted in all cases. OSHA and other regulatory agencies also require written periodic inspections of cranes and other equipment by a competent person. Records should be kept of all inspection and maintenance activities so that supervisors can monitor them and have ready access to the records in case of inspection. Before each shift, it is the equipment operators responsibility to thoroughly inspect the equipment. A walk-around inspection should be conducted before climbing aboard the machine. The following should be inspected regularly: Missing nuts, bolts, pins, loose fittings and couplings, frayed cables and hoses, and loose tracks and pads are examples of defective items to be identified and corrected. Cracked paint can also be a sign of underlying structural weakness and should be investigated. Fluid levels in the battery, hydraulic system, fuel supply, brake system, cooling system and engine (lubrication) should be check daily, as well as tire inflation. All filler plugs, dipsticks, and caps should be secured daily also. Operators must never use their hands to check for hydraulic leaks and an open flame must never be used to check fluid levels or to look for leaks on equipment. Equipment surfaces and the ground beneath parked machinery should be checked daily for evidence of leaking fluids. Check to ensure that all guards and falling object/protective rollover protective systems are in place and in satisfactory condition.


Machine guards are required at all pinch points and on all cables and pulleys near points of operation as well as at their adjustments, entrance, and exit. Guards, in the form of control level cover, lockable ignitions, and padlocks on starter-engaging rods may be used to prevent accidental activation of equipment. The second phase of a daily inspection is a survey of the job site. Areas should be identified where the ground is loose or muddy or where heavy traffic can be expected. When heavy equipment is to be used on floors, the intended loads to be imposed upon the floors should be checked in advance to determine their safety on the basis of accepted engineering requirements. All floor openings should be protected by securely fastened bumpers that will prevent equipment from running over an edge. The third phase of inspection takes place immediately before starting the equipment. The operators cab should be cleared of tools, personal items and other debris that could obstruct the movement of controls or visibility. A fire extinguisher should be mounted within easy reach of the operator. It should be checked regularly to ensure it is in working order. Before ignition, all controls should be placed in the ,,neutral position. The control panel should be surveyed for ,,lockout tags. When a ,,lockout tag has been displayed, the equipment must not be started until the person who placed the tag removes it. After start-up, all gauges should be checked for proper readings. The engine speed controls, lights horns, back-up alarms, steering and all other controls should be tested. The operator may not work the controls until he/she is completely familiar with them (or has provided documentation that he/she is certified for the equipment). The operator must pay attention to unusual noises or odors from the equipment. In the event there is something unusual, it should be investigated before work proceeds. The operator must report faulty equipment to the site supervisor immediately. No matter how important a job is, it cannot be done safely with defective equipment.

Operation of heavy equipment presents additional hazards in wet or freezing conditions. It is important for workers to remain alert to this. Cold temperatures can reduce the responsively of hydraulic equipment. Hydraulic actuated booms, buckets, shears, and other attachments should be warmed up before operating them with either no loads or light loads. Ice, frost, and fog should be cleared from windows, so as not to limit visibility. Starting fluids which contain flammable ether, should be used with extreme caution and only at with the express permission of the site supervisor. Fires should never be used to thaw out frozen tracks.


To guarantee the safe operation of heavy equipment, it is essential that all operators are thoroughly familiar with parking and shutdown procedures. Vehicles should be parked in designated parking areas and not left near falling or combustible debris. When a vehicle must be parked on an incline, wheels or tracks must be carefully blocked/chocked. Equipment shutdown procedures, whether for long or short-term, should follow the operators manual. Generally, all controls should be relieved and all elements should be at rest. Clutches should be disengaged and brakes left on. At the end of the shift, adequate precautions should be taken to prevent unauthorized start-up. Ignitions, as well as cabs, should be locked whenever possible. Many times, Staton jobs are located in communities with a history of illegal environmental activism. Businesses have been targeted with vandalism to their equipment and job sites. All efforts should be made to prevent such activities, as it can represent serious threats to worker safety, public safety, lost productivity, lost profits and unwanted media attention. Therefore, it is each employees responsibility to ensure that all equipment is secured as well as possible at the end of a shift. If an employee feels there are vulnerabilities to the equipment or the job site, he/she must notify the site supervisor before leaving for the day. 6.2 Heavy Equipment Maintenance Maintenance work can be hazardous if not performed carefully and according to safe work practices. Equipment that breaks down on the job must, when possible, be moved to a safe location before repair work is started. Before any worker crawls into or under a machine, the wheels/tracks must be blocked, and the rig must be out of traffic. When equipment is being worked on in a closed space, the machines exhaust must be directly vented to the outside and adequate ventilation must be provided to prevent poisoning from exhaust fumes. The equipment repair and/or owners manual should be consulted before the repair of the equipment. All controls and gears should be in neutral position, with the engine stopped and the brakes set, unless the work being performed requires otherwise. Before beginning maintenance work, the starting controls should be locked out and tagged. The repair person is then responsible for removing the tags when the repair work is completed. The key should also be removed if possible while the repair work is being done.


Changing batteries on machinery can cause unnecessary injuries. Therefore, special care and attention should be taken when changing batteries. Battery acid will burn the skin, eat holes in clothing, and cause blindness if splashed in the eyes. If a worker comes into contact with battery acid, immediately flush the area with large amounts of water. Acid in the eyes requires immediate and continuous flushing with water until professional medical attention can be obtained. To prevent this serious injury, appropriate eye protection must be work whenever batteries are being serviced. When replacing batteries, it is always the ground clamp that is removed first and replaced last. In order to prevent sparking at the posts when using a battery charger, the charger should be turned on only after the leads are connected to the battery posts and must be shut off before the leads are removed. Lead-acid batteries generate a combination of hydrogen and oxygen when charging and discharging. This mixture of gases is extremely explosive, so sparks and flames must be avoided in the vicinity of the battery. When charging or jump-starting a battery, cell caps should be removed, and the openings covered with a damp rag. When jumpstarting a dead battery, the positive terminal on the dead battery should be the first connection. The other end of the positive cable must then be connected to the positive terminal or the good battery. Next, the negative cable must be connected to the negative terminal on the dead battery and finally the other end of the negative cable must be attached to the engine block or frame of the good vehicle. To prevent explosions, flashlights should be used to check electrolyte levels, and sparks at the battery terminals must be avoided. 6.3 Machinery for Transport Oversized machinery that is driven on public roads should be equipped with warning flags on overhanging structures, with ,,wide-load signs and, if necessary, with ,,slowmoving vehicle signs. Lights should be on for safety at all times. Oversize vehicles must conform to state standards, which usually require special permits. When required, separate vehicles should escort both slow-moving and oversized vehicles. Prior to transporting any heavy equipment, whether driven, towed or loaded on a flatbed trailer, a specific route should be planned whenever possible. Clearances on bridges, tunnels and other obstacles should be checked, with adequate allowances made for overhanging booms. The height and weight of the machine should be obtained and verified. The ramp and truck or tractor/trailer must be adequate to carry the load. Congested areas present additional hazards and should be avoided whenever possible. Workers who drive machines or trucks must be thoroughly familiar with the equipment. It is the workers responsibility to inform the site supervisor is he/she is not familiar with a vehicle to which he/she has been assigned to drive or operate.


Chock blocks should be placed in front of the trucks wheels to eliminate the possibility of it moving. Both the bed of the truck and the wheel or tracks of the equipment should be cleaned of all clay, soil, oil or grease which might cause the equipment or workers to slip. 6.3.1 Loading The ideal location for loading equipment is dry, level ground. The stability of the equipment is increased when booms, buckets and blades are kept as low as possible. Most operators manuals recommend the direction in which the machine is most safely loaded onto the bed. When this recommendation is followed, the danger of tripping is minimized. Workers other than the operator driving the equipment on or off the truck or trailer should stay a safe distance away from the loading/unloading operations. As soon as the machine is properly situated, the buckets, blades or booms should be lowered to the bed. The engine is then turned off and the key removed from the ignition. It is important that open exhaust stacks be covered. This is particularly important on machines with turbochargers, which can ,,free-wheel in the absence of oil pressure and damage the bearings. When the shift lever is in the ,,park position or in low gear, and the parking brake is applied, the equipment is ready to be secured. 6.3.2 Securing The equipment must be secured to the truck with rated chains or cables. It is essential that when tie-downs are tightened, they are not in contact with hoses, hydraulic cylinders, valves, rods or tires. The use of ratchet binders can be used. ,,Cheaters should not be used under any circumstances. Usually, the operators manual recommends tie-down points. If these are not available, recommended tie-down points on crawlers are the track shoes (just above the sprocket) and idlers (front, center, rear). On wheel machines, the points are axle housings, front axle members, tow hooks, drawbar mounts and openings in wheels. Equipment should never be transported, even over short distances, unless it is properly secured. Unloading procedures should be followed in the reverse order of those presented above. 6.4 Safe Use of Material Handling Equipment (29 CFR 1926.602) 6.4.1 Loaders Front-end loaders can be hazardous because the bucket limits visibility. When a load causes the loader to tip forward, the operator should not panic and apply the brakes. Instead, the load should be immediately lowered. To increase both stability and visibility, loads should always be carried near the ground. Loads must never be carried overhead. Buckets must never be used for brakes, except in emergencies. Whenever possible, loads should be dumped with the wind to the operators back.


A FOPS/ROPS canopy should be installed on all loaders used at demolition sites. This is particularly important because of exposure to falling debris while wrecking a building. Seat belts must be worn in all equipment due to the danger of roll overs. 6.4.2 Basements Basements or voids should be located prior to demolishing the structure, and all equipment operators should know their exact location. If basement areas are going to be used to hold debris, caution should be used when running over the area with heavy equipment. Visibility can be restricted when coming out of a basement area. Caution must be exercised to make sure workers and other equipment are out of the way. 6.4.3 Stockpiling Debris When stockpiling or crushing debris, operators should be constantly on the alert for loose pieces of re-bar (reinforcing steel) which can lodge in the tracks. Re-bar lodged in the tracks can be extremely dangerous to nearby workers and the operator. 6.4.4 Attachments All attachments should be OEM (Original Equipment Manufacturer) approved. A loader with or without an attached pole or similar device should not be used to wreck any structure with a maximum height in excess of 40 feet. 6.5 Safe Use of Trucks (29 CFR 1926.601)

The driver is primarily responsible for keeping his/her equipment in a safe condition. Trailer hookups, tires, and safety chains should be inspected before each use. Operators must provide documentation or demonstrate that they are trained in the operation of air brakes. Brakes should always be tested before entering a highway from a job site. Drivers must also provide documentation that they have the proper Commercial Drivers License (CDL) to drive a particular truck or combination truck and trailer unit. 6.5.1 Loading Demolition dump trailers used to haul small debris should have a platform or ladder in front. The driver should direct the loader operator in loading the trailer to prevent


uneven distribution of the debris and overloading. Load large pieces of concrete or debris carefully. Dropping large pieces can cause severe damage to the truck or trailer and may knock the driver off the truck. When loading a truck with long steel beams or when loading steel scrap with an electric magnet, it may be advisable to have the driver stand away from the truck. Drivers must wear hard hats and may need eye protection when out of the cab. Seat belts and automatic back-up alarms should be used as well. When loading trailers, caution should be used not to spill debris over the far side of the trailer. If loading is performed in the street, no pedestrians, workers or vehicles should be allowed next to the loading operation. Equipment operators must cooperate with the driver in distributing the load as evenly as possible. This helps to prevent overloading on one side and possible rollovers of the truck at the dumpsite. After the trailer is loaded, the driver should make certain no pieces of debris extend above the legal height or hang over the sides of the trailer. Any loose debris lying on the rails of the trailer should be cleaned off, so it does not fall on a highway or road. If necessary, the debris should be wetted and/or tarped. 6.5.2 Hauling The following should be adhered to during hauling: Disengage the Power Take-Off (PTO) prior to traveling. On dual axle tractors, check to make sure the interlock switch is disengaged after entering the roadway. During repairs or maintenance, the bed of the trailer or debris box should be blocked up and secured when the hoist is in the extended position. 6.5.3 Dumping The following should be adhered to during dumping: When dumping end dump trailers, all axles and wheels should be on level ground. If a soft spot develops while dumping, the trailer should be lowered and reset at another location. Ensure other equipment and personnel are not on either side or in back of the trailer during the hoisting and dumping process in the event of a rollover. Dumping during high winds is discouraged. If it is necessary to dump during high winds, dump with the rear of the trailer to the wind. The bed should not be raised when the wind is perpendicular to the side of the trailer. Overhead obstructions such as utility lines should also be watched when dumping.


Tailgates, especially single barn door types, should be opened when standing to the side, clear of any falling debris when the door is opened. After dumping, tailgates should be properly secured. Keep tools and objects in the cab of the truck secured. Loose objects can be deadly missiles in the event of a rollover or accident. The driver should never stand on the step or running board of the truck with the door open during the hoisting and dumping operation. The driver should stay in the cab with the doors closed. Unless required for training purposes, passengers should not be in the cab during the hoisting and dumping. 6.6 Safe Use of Cranes (29 CFR 1926.251, 1926.550, 1926.859 (a-d))

Cranes are an integral part of the demolition industry. Due to their size and complexity, the potential for property damage and human injury is very large. Cranes and hoisting equipment account for a high percentage of occupational injuries, many of them fatal. The guidelines in this section outline the most critical considerations when using cranes. They should be combined with the detailed and specific instructions provided in the operators manual, the expertise of professionals, and the care and know-how of experienced personnel. While crane safety starts on the management level with the proper selection and training of personnel, every worker is responsible for their own safety and that of their co-workers. Like any other tool, a crane should be appropriately matched to the specific demolition job. The crane should be matched to the weights, dimensions and maximum lift height and radii of the heaviest and largest loads. The number and frequency of lifts and whether or not precision placement will be needed are other important factors. It should be noted that some truck cranes are not rated to swing a load 360 degrees and that must considered when planning a job. When determining load capacity, a 5% working margin should be the minimum considered. The conditions of the supporting ground or structure, access roads, obstacles, sufficient space for assembly, operation, and dismantling are all essential factors in selecting the appropriate crane. All major crane components should have a permanent manufacturers nameplate with a model number and year, serial number, and unit weight. Identification numbers should be marked on basic removable parts to ensure that parts are used only on the machines for which they were intended. Switching parts, either accidentally or purposefully, is a dangerous practice and should never be done without the express certification of a professional engineer.


6.6.1 Load Charts Every crane should be equipped with a load chart posted in the operators control station. The chart should include: nameplate identification information; load ratings for the boom at all stated operating radii or angles for different counterweights, boom lengths, and types; jib ratings; and the method for calculating boom-jib ratings. Those ratings that are due to structural limitations rather than stability must be identified. The operator should be warned that the load charts make no allowances for round conditions, wind, operating speeds, swinging loads, or failure to meet specifications such as tire inflation. Other data to be included on the load chart can include: gear change instructions, recommended parts of hoist reeving, size and type of rope for various loads, drum data, line speeds and pull, rope spooling capacity, tire pressures, and limits for low temperature and high wind operation. If the crane is equipped with a telescopic or hydraulic boom, relevant information should also be posted. 6.6.2 Crane Features Recommended safety devices for cranes include: boom angle and length indicators (where applicable), shock-absorbing boom stops and boom hoist safety shut-offs, and an operator-actuated audible warning signal. When balling with a crane, the windshield should be kept closed. Glass must be a minimum of safety glass and ideally ,,bulletproof glass. Covering the glass with a protective steel screen may also be advisable as long as visibility is not compromised. Regular inspection of equipment is the only way to ensure safety and reliability. As stated previously, the operators manual is the most important guide. However, it should be noted that the manufacturers inspection and maintenance schedules are based on the minimum safe operating intervals for average conditions. Equipment used more than this may need more frequent and more detailed inspections. These inspections must be documented. An inspection should always be carried out before the use of newly purchased or rented equipment and any equipment that has undergone repairs, overhauls, or design modifications. The following should be checked daily on crane equipment: Lubrication Batteries Air tanks Brakes Clutches Wire ropes Swivels Components used for lifting, swinging and lowering Jibs and booms


Tires Boom and tower Counterweights Limit switches Slewing ring bolts Walking surfaces should be kept clean Fluid leaks Exposed moving parts are guarded Ground conditions

In addition, a positive acting device to prevent contact between the load block or overhaul ball and the boom tip (anti-two-blocking device), or a system which deactivates the hoisting action in a two-blocking situation may be used. A thorough annual inspection of the hoisting machinery must be made by a competent person or by a government or private agency recognized by the US Department of Labor. A record must be maintained of the annual inspection. 6.6.3 Hydraulics Hydraulics create special problems when maintaining cranes. If the boom, outriggers, and other attachments are supported by pressurized oil, they must lowered if possible. If they cannot be lowered, they should be secured and blocked. The control levers should be worked through all positions to relieve any trapped pressures. Finally, hydraulic tanks should be gradually de-pressurized by loosening filler caps before removing them. 6.6.4 Machine Assembly and Set-Up Over half of all crane accidents result from oversight or mistakes made during the setup and placement process. Following the manufacturers instructions for assembly and disassembly, using the correct parts, and taking proper precautions can reduce this startling figure. No matter how good the operator and machinery are, poor work in preparing the work area can result in unsafe operation. Specific considerations for boom assembly include: The use of special suspension equipment on long booms The use of the cranes gantry in its highest position Proper pendants of equal length for the boom The use of short boom sections close to the boom foot Leveling the crane Checking that the boom hoist limiting device is in working order Fully extend and block the outriggers and get the wheels off the ground Ensure the ground conditions are safe Never work under the boom


6.6.5 Use of a Signalman

An authorized signalman should be appointed to work with the operator. The operator should take directions using standard hand signals or approved electronic communication equipment for the single designated signalman. If 2-way radios are used for signaling, they should be used on a private frequency only. CB radios are not to be used. Hand signal instructions to crane and derrick operators, complete with instructions, should be posted on the job site. If the operator loses sight of the signalman, he/she should stop operation immediately until the signalman is located. 6.6.6 Operator Safety Responsibilities In addition to knowing the machine and its limitations, the operator should take the following steps to ensure everyones safety: The swing radius of the crane should be clearly marked Loads must never be swung over anyones head When moving the crane, the operator should sound the horn initially and while traveling If engaged with a load (pick and carry operation), the operator should keep in mind that the manufacturers rating are intended only for stationary and level conditions Capacity or near capacity loads should not be transported The cranes outriggers should always be used when lifting. If the crane lifts while supported by its tires, safe procedures involve checking the wheels, applying air brakes, and keeping the carrier engine running. Crane mats can be used under the cranes tracks or outriggers Utmost caution should be exercised in every aspect of crane operation The load weight is the single variable in mobile crane operating that is always changing. Its effect should never be overlooked. It is very important to determine the weight of any load before rigging, and an allowance should be made for unknown factors. Rigging equipment should be included in the loadweight. When approaching the upper 25% of the cranes rated capacity, it is a good time to measure the load radius.


6.6.7 Demolition Ball

When a crane is being used with a demolition ball, the ball weight must not exceed 50% of the safe load of the boom at maximum length and angle of operation, or 25% of the normal breaking strength of the supporting line, which is less. The booms swing must not exceed 30 degrees from the centerline (front to back) of the crane mounting. The load line and swivel-type attachment must be checked at least twice daily. The demolition ball should be attached to the load line with a swivel-type connection to prevent twisting of the load line. It should attached by a positive means in such a manner that the ball cannot become disconnected by slack in the load-line or other causes. The use of tires for the swivel connection is prohibited. Under no circumstances should a person be allowed to ride on or work from a demolition ball. Smoothness is an obvious key to safety, as sudden movement of changes in speed can be hazardous. The use of taglines can help control the load. Workers must never wrap tag lines around their hands or other parts of their bodies. Though smoothness may be difficult to achieve when using a demolition ball, it is nonetheless a worthwhile goal. Aim is important, since missing the target may tip or overload the machine, and a wild swingback may hit the boom. Balls must never be swung over anyone, should not be hung from jibs attached to main beams, and should not be used on hydraulic booms. 6.6.8 Clamshell Bucket The clamshell bucket also presents special problems. The operator should be ready to release the closing line if an overly heavy weight is bitten off. When using a clamshell bucket, special care must be taken by workers to stay clear of debris hanging out of or falling from the bucket. Rigging the load properly is an integral part of safe crane operation. All equipment, ropes, and slings should be in good condition, free of kinks or bends and not exposed to corrosive, rusting or welding operations. If defects are found during inspection, the equipment should be destroyed so that it is not inadvertently used. The working


capacity of all rigging equipment should be known and should exceed that required for the loads weight radius. Putting the loads center of gravity under the lift points should stabilize the load. When the load has been properly rigged, the load is free, slack line conditions have been corrected, and multiple lines are free of twisting, nonessential personnel should be told to leave the area. No worker should ever be underneath a suspended load, and all personnel should stand clear when slings are being withdrawn. Workers must also take care to keep their hands away from pinch points. 6.6.9 Electrical Hazards

Electrocution is the largest cause of crane fatalities. The problem of cranes and electrical hazards simply cannot be overstated. Live power lines have areas called the ,,absolute limit or approach. No exceptions to the rule prohibiting entry into this area can be made unless the line has been insulated or de-energized. Line Rating 50 kV or Below Above 50 kV Minimum Clearance--Crane or Load to Lines 10 feet 10 feet plus 0.4 inch for each 1 kV over 50 kV or twice the length of the line insulator, but never less than 10 feet

A signalman should be assigned to warn the operator when he/she is nearing the limit of approach. The operator must be notified when he/she is within a booms length of the limit. Even crane safety devices specifically designed to protect the operator and machine from electrical contact are limited in value. These two rules: (1.) the use of a signalman and (2.) the limit of approach can never be compromised. Other precautions which can be taken are: grounding the crane, relocating the power lines, having the utility company insulate the power lines, warning ground personnel to stay clear of the machine, and checking with the signalman before touching the load. The utmost care must be taken around radio transmission towers as they can cause the boom to become electrically charged. If, despite all precautions, the crane makes contact with a live circuit, the operator should stay inside the cab unless there is some more immediate danger such as the cab being on fire. All personnel should stay away from the machine, its load, and the surrounding area, which will also be charged. The operator can try, by himself, to back the crane well away from the power line or to lower the boom and then move away from the line. If he/she cannot do so, he/she should wait for the electrical authorities to deenergize the line. If the operator is forced to leave the machine, he/she should jump


completely clear from it and land with his/her feet together. Stepping down, or allowing any part of his/her body to touch the machine and the ground at the same time can result in electrocution. When on the ground, the operator must maintain his/her balance, shuffle slowly across the ground or hop on one foot until he/she is at least 30 feet away from the rig. If his/her feet are planted simultaneously in areas of differing voltage, the worker could be killed.


Chapter 7 Handling of Hazardous material

Handling of Hazardous Material


This chapter deals with regulations of the U.S. Occupational Safety and Health Administration (OSHA) and the U.S. Environmental Protection Agency (EPA) for asbestos, PCBs and lead. 7.1 Safe Handling of Asbestos (29 CRF 1926.1101 and 40 CRF Part 61, Subpart M)

Asbestos has been used extensively as a construction material. The U.S. EPA has estimated that 30 million tons were used between 1900 and 1980 in the United States. When it is present in a structure that will be demolished, special work practices are required in order to protect both human health and the environment. Asbestos is a term for a group of naturally occurring minerals that separate into fibers. There are two basic mineral groups of asbestos, Serpentine and Amphibole. There are six types of asbestos: Chrysotile, Crocidolite, Actinolite, Tremolite, Anthophyllite, and Amosite. Chrysotile asbestos accounts for about 95% of the worlds commercial asbestos use. Asbestos fiber possesses a high-tensile strength, is chemically inert, is non-combustible, and is heat resistant. It has a high electrical resistance and has good sound-absorbing qualities. It can be woven into cables, fabrics, or other textiles. It can also be matted into paper, felts and mats. Asbestos fiber resists acids as well. Chrysotile is the only type that is slightly soluble in hydrochloric acid (HCL). These properties have made asbestos attractive for many uses. Demolition workers may encounter asbestos in the insulation on pipes, furnaces, reactors and boilers. Asbestos can be found in sprayed-on/troweled-on materials used as fire protection, sound suppression, or decorative coatings. Many flooring materials, wallboards, and ceiling materials also contain asbestos. Many regulations refer to asbestos as ,,ACM (asbestos containing materials). Unfortunately, the fibrous nature and durability that made asbestos attractive as a construction material make it a troublesome environmental and employee health problem. The fibers are not easily destroyed and they break down into infinitely smaller


fibers. Because of their aerodynamic shape and microscopic size, these fibers can remain airborne indefinitely. The key to good work practice is reducing exposure to asbestos by preventing these fibers from becoming airborne. Thus, the possibility of inhalation or ingestion of any fibers that might escape is reduced. 7.1.1 Health Effects of Exposure to Asbestos (29 CRF 1926.1101,

Appendices H and I)

Although asbestos has been in use for over 2000 years, it was not until the 20th century that its health problems became widely known. Asbestos fibers that are either inhaled or ingested can ultimately cause health problems. If asbestos fibers are inhaled, asbestosis, mesothelioma, lung cancer and other respiratory ailments may result. Manifestations may typically appear as later as 20 to 40 years after exposure. There is evidence of a dose-response relationship. However, there is no indication of how much asbestos one must be exposed to in order to contract one of these ailments. Studies indicate that an exposure to one fiber or any fraction thereof can be problematic. Smoking is particularly hazardous for those working around asbestos. Studies have shown that lung cancer is up to 92 times more frequent in asbestos worker who smoke than in the non-smoking general population. Therefore, for many health reasons, workers are encouraged to quit smoking if at all possible. 7.1.2 Applicable Government Regulations The U.S. EPA and OSHA have regulations relative to asbestos that include work practice and disposal procedures designed to protect human health and the environment. It is important to note that local and state governments may have slightly different requirements. These should be checked before beginning a job. OSHA divides asbestos removal into four classes with specific requirements for each class. The minimum training requirements for a worker in each class are as follows: 1. Class I, Model Accreditation Program (MAP) found in 40 CFR Part 763, Subpart E, Appendix C, 32 hours; 2. Class II, Model Accreditation Program (MAP) found in 40 CFR Part 763, Subpart E, Appendix C, 32 hours; 3. Class III, Model Accreditation Program (MAP) found in 40 CFR Part 763.92 (a)(2), 16 hours; 4. Class IV, Model Accreditation Program (MAP) found in 40 CFR Part 763.92 (a)(2), 2 hours. 7.1.3 Planning


The first thing that should be done is to determine whether there is asbestos present at a job site or not. This determination is best left to an approved independent professional firm that specializes in conducting environmental surveys, including asbestos. However, as a practical matter, OSHA defines Presumed Asbestos Containing Material (PACM) as thermal system insulation (TSI) and surfacing material (SM) found in buildings constructed no later than 1980.These materials must be presumed to contain asbestos unless one can prove otherwise. One may disprove this definition by sampling the material in question following these procedures: 1. The samples must be taken in accordance with the Asbestos Hazard Emergency Response Act (AHERA); 2. The samples must be taken by a qualified inspector or certified industrial hygienist; 3. Analysis of the samples shall be performed by persons or laboratories with proficiency demonstrated by current successful participation in a nationally recognized resting program such as the National Voluntary Laboratory Accreditation Program (NVLAP) or equivalent. During the planning phase, it is important to know whether the asbestos containing material is friable or non-friable since removal and disposal requirements vary considerably depending on which type is present. Friable asbestos is any materials that contains more than 1% asbestos by weight and can be easily crumbled or reduced to powder when dry by hand pressure. All demolition work, whether asbestos is involved or not, requires written notice to the Federal EPA 10 business days prior to the start date of the work. Removal that includes asbestos in amounts greater than 260 linear feet on piping, 160 square feet on other facility components and/or 35 cubic feet on other facility components that were not previously identified also require written notice to the Federal EPA 10 business days prior to the start date. If asbestos-containing material is determined to be friable, EPA regulations will apply not only to the work practices that must be used in order to prevent the release of fibers but also to the disposal requirements in order to ensure the same disposal of asbestoscontaining materials. OSHA regulations, dependent upon airborne concentration levels, cover work practices and control methods for the workers at the demolition site. Basically, the EPA covers the environment, and OSHA covers human health.

7.1.4 Preventing Fibers from Becoming Airborne Two techniques can be used to meet these requirements: local ventilation with a HEPA filter or collection device and wet removal techniques. EPA also requires certain work


practices to prevent emissions of particulate asbestos materials to the outside air. Essentially, the EPA requires no visible emissions. Local ventilation with HEPA filter or collection device specifications can be found in 29 CFR 1926.1101 (g), referred to as a Negative Pressure Enclosure (NPE). When utilizing wet removal techniques, the following should be considered: 1. Asbestos should be wetted down with a fine spray since high-pressure concentrated streams may not properly wet the material; this can force off chunks of asbestos material and use larger amounts of water; 2. Do a thorough wetting with a minimum of water. This keeps wetted material off walking surfaces where it could present a slipping hazard to workers; 3. Surface active ingredients called surfactants can be added to the water to increase its ,,wetting capability. These surfactants provide for better wetting, enabling the amended water to penetrate further into the material, and it requires only about 1/3 the amount of water needed when surfactants are not used. The disadvantages are that the use of surfactants add to material costs, make footing more hazardous than regular water, and can cause eye irritation. The EPA calls for the suspension of their wetting requirements when the temperature falls below freezing (0C-32F) if a local exhaust ventilation and collection system designed and operated to capture the asbestos are used. At that point, only asbestos material which can be removed in sections is allowed to be worked on. Furthermore, the temperature must be taken and recorded at the beginning of the shift, midway through the shift and at the end of the shift. Dry method removal around high voltage, is also allowed. Glove bags should be used, whenever possible, during approved dry removal situations. The EPA also requires certain work practices to prevent emissions of particulate asbestos material to the outside air. Require work practices are found in 29 CFR 1926.1101 (g). In order to prevent emissions of particulate asbestos material to the outside air, the EPA requires the following procedures: 1. The removal of all material shall occur before the wrecking, dismantling, or intentional burning of the structure begins. The wetting requirements outlined above are in effect at this time; 2. When stripping asbestos-containing material, adequate wetting is required to ensure that no emissions are released to the outside air; 3. When removing asbestos material in sections from pipe or ductwork, adequate wetting is also required. EPA regulations require that such units shall not be dropped or thrown to the ground but shall be carefully lowered to ground level;


4. All asbestos material that has been removed shall be adequately wetted to ensure that it remains wet during all of the remaining stages of demolition of handling; 5. When removing asbestos material from more than 50 feet above ground level, except that material removed as sections, the EPA requires the use of dust-tight chutes or containers. 7.1.5 Protective Practices for Workers These practices are prescribed by OSHA and cover 6 major areas of regulation designed to protect the demolition worker when handling asbestos material. These 6 areas are: Area Notification of the worker Issuance of protective clothing Monitoring of the workers exposure Respirator selection and use Recordkeeping Medical surveillance Regulation 29 CFR 1926.1101 (k) 29 CFR 1926.1101 (i) 29 CFR 1926.1101 (f) 29 CFR 1910.134 29 CFR 1926.1101 (n) 29 CFR 1926.1101 (m)

1 2 3 4 5 6

Notification of Workers Workers will be notified that asbestos is present at the job site and that appropriate steps are being taken to control their exposure to it. ,,Danger signs containing the relevant information will be posted at job sites if the exposure level exceeds the Permissive Exposure Limit (PEL) of 0.1 fibers per cubic centimeter as a Time-Weighted Average (TWA) over an 8-hour sampling period or if there is a reasonable possibility that it may exceed the PEL. Workers should not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in the regulated area. OSHA defines a regulated area in 29 CFR 1926.1101 (b) and (e). Workers will be notified of any exposure monitoring results as soon as possible following their receipt. Workers will be given the physicians written opinion within 30 days of its receipt. Issuance of Protective Clothing Workers will be provided with protective clothing consisting of coveralls, gloves, head coverings, and booties if the asbestos fiber concentration level exceeds the 0.1 fibers per cubic centimeter (TWA) and/or the Excursion Limit (EL) of 1.0 fibers per cubic centimeter averaged over a 30 minute sampling period. Protective clothing will also be provided to employees who are conducting Class I work where more than 25 linear feet or 10 square feet of asbestos-containing or presumed asbestos-containing materials are being disturbed. Protective clothing may also be


required when an initial exposure assessment and/or a negative exposure assessment have not been done yet. Protective clothing used during asbestos removal must never be taken home or worn off the job site. Monitoring Worker Exposure OSHA has established a PEL of 0.1 fibers per cubic centimeter of air over an 8-hour TWA. Decontamination areas, clean rooms, and showers will be provided for exposures over the PEL and/or EL. Smaller jobs may be exempt from some of these requirements if there has been a negative exposure assessment for the type of job. (This negative exposure assessment must job specific, or it must be virtually identical to a similar job that was done within the last 12 months). Air monitoring for asbestos is accomplished by collecting air through a 25 millimeter, mixed cellulose ester (MCE) filter attached to a sampling pump in the workers breathing zone. The asbestos fiber counts on the carefully preserved filter will be analyzed at an approved laboratory. Respirator Selection and Use The use of respirators is required to safeguard workers while removing asbestos. The type of respirator that must be worn by workers depends on the concentration levels in a given area. If the concentration of asbestos fibers is reasonably expected to exceed 100 fibers per cubic centimeter on an 8-hour TWA, a type C, full facepiece, supplied air respirator operated in pressure demand mode equipped with an auxiliary positive pressure self-contained breathing apparatus is required. Respirators should be fit-tested once a year. Respirators shall be worn during the following circumstances: Class I jobs Class II jobs where the asbestos-containing material is not removed in a substantial intact state Class II and Class III work where the asbestos-containing material is removed without utilizing wet removal methods Class II and Class III work where there is not a negative exposure assessment Class III work where TSI and SM or PACM is disturbed Class IV work when this work is done within regulated areas where respiratory protection is already required When the employee is exposed to the PEL or EL When there is not a negative exposure assessment A Powered Air-Purifying Respirator (PAPR) will be issued to an employee if he/she requests one and it will provide adequate protection for its intended use


Type C respirator with an auxiliary positive pressure self-contained breathing apparatus within the regulated area where Class I work is being performed for which a negative exposure assessment has not been performed A half-mask air-purifying respirator for Class II and Class III work for which a negative exposure assessment has not been performed. Attention: Air-purifying respirators should never be worn in environments deficient of oxygen since they do not supply air to the user. They filter only the existing ambient air in the work area where oxygen must be present at levels between 19.5% and 23.5%. A written respirator plan will be maintained in accordance with 29 CFR 1910.134. The following are more basic guidelines for respirator use: Measured 8-Hour, TWA Exposure Not in excess of 1 fiber/cc (10 x PEL) Not in excess of 5 fibers/cc (50 x PEL) Not in excess of 10 fibers/cc (100 x PEL) Type of Respirator Half-mask air-purifying respirator, other than a disposable respirator, equipped with high-efficiency filters Full facepiece air-purifying respirator equipped with high-efficiency filters Any powered air-purifying respirator equipped with high-efficiency filters Any supplied-air respirator operated in continuous flow mode Full facepiece supplied-air respirator operated in pressure demand mode Full facepiece supplied-air respirator operated in pressure demand mode equipped with an auxiliary positive pressure self-contained breathing apparatus

Not in excess of 100 fibers/cc (1000 x PEL) Greater than 100 fibers/cc (1000 x PEL) or unknown concentration

Recordkeeping OSHA requires that employers maintain records of all asbestos-containing exposure monitoring for a period of 30 years. OSHA also requires employers to provide preplacement, annual and termination medical exams for all employees exposed to asbestos. These medical surveillance records will be maintained for the duration of employment at Staton plus 30 years. Training documentation will also be maintained for the duration of employment plus 1 year.

Medical Surveillance Medical surveillance will be provided for workers that are engaged in Class I, II, III work for 30 days or more in one consecutive 12-month period, for workers that are exposed


above the PEL for 30 days or more in one consecutive 12-month period, and for workers who will wear a negative-pressure respirator. 7.1.6 Disposal of Asbestos (40 CFR Part 61, Subpart M, Section .150/49 CFR

Parts 171 and 172)

Both EPA and OSHA have regulations concerning the safe disposal of asbestoscontaining material. After removal, the wetted asbestos material must be placed in sealed, leak-tight, double plastic bags with a minimum thickness of 6-millimeters, or it must be placed in metal or fiber drums. The bags must be labeled with a warning label shown. However, the material is exempt from these labeling requirements if the asbestos content is 1% or less. Current regulations require that the asbestos waste material be sealed in ,,leak-tight containers. This includes sealed plastic bags. However, the disposal practices of certain landfill operators might require that the sealed bags be placed in drums. The U.S. Department of Transportation (DOT) requires that asbestos be transported in containers that prevent the leaking of hazardous material during transit. The U.S. DOT also requires placarding/labeling of containers in which hazardous materials are transported as well as manifesting of each shipment. The asbestos waste material in the sealed leak-tight bags should be deposited at an approved waste disposal site. The site supervisor or other management personnel at Staton will determine where the approved sites are located. Disposal receipts/manifests will be retained for appropriate recordkeeping. Managers will also coordinate any needed assistance from EPA and/or OSHA. Staton workers should refer any government agency representative who contacts him/her to the site manager or other Staton management personnel. Unless directed by a supervisor, no Staton employee should provide any information to any government agency representative. 7.2 Safe Handling of PCBs (40 CFR PART 761) Demolition workers may encounter Polychlorinated Biphenyls (PCBs) in transformers and capacitors that are part of a structures electrical system. PCBs are organic chemicals that have been used extensively in electrical equipment, heat transfer systems, and coating materials. The chemical is highly stable, possesses a low flammability, and is an excellent medium to sustain an electrical field. PCBs are usually a heavy oil-like liquid that is clear or amber in color. Oil with a high concentration of PCBs often has a distinctive chemical smell. The chemical was first manufactured in 1929 and the EPA estimated that in 1979 about 38% of all mineral oil transformers in service contain PCBs.

7.2.1 Health Effects of Exposure to PCBs


Studies performed on animals exposed to PCBs indicate that the substance is a potential cancer-causing agent to humans and can cause liver damage and stomach problems. An acne-like skin irritation called chloracne is a common health effect from exposure to PCBs. PCBs do not break down into harmless materials after they enter the environment and can move up the food chain to humans. 7.2.2 Applicable Government Regulations Because of the harmful nature of PCBs, Congress enacted legislation as part of the Toxic Substances Control Act (TSCA), to deal with the problem. Under TSCA, the EPA banned the production of PCBs in July of 1979 and developed regulations for their marking and disposal. They also developed a ,,gravity-based penalty assessed on the basis of the seriousness of the violation. A penalty of up to $25,000 a day may be assessed for a major violation, such as a spill of over 1,100 gallons of PCB-containing liquid. Penalties of lesser amounts are assessed for violations such as improper storage of failure to use required PCB warning labels on equipment containing PCBs. The National Institute of Occupational Safety and Health (NIOSH) has developed a recommended occupation exposure standard for PCBs of 1.0 micrograms total PCBs per cubic mete or air (µg/m3), determined as a TWA concentration for up to a 10-hour workday, 40-hour work week. 7.2.3 Planning There are two goals when dealing with PCBs: to protect the worker and the general public from PCB exposure. A less goal may to salvage a valuable piece of equipment. Careful planning should be able to accomplish all of these goals. The first task is to determine if PCBs are present at a job site. The easiest way to do this is to inspect the nameplate on the equipment for the trade name of the insulating fluid. Monsanto Corporation, the principal manufacturer of PCBs in the U.S., sold them under the trade name ,,Askarel. Other companies marketed PCBs under other trade names such as: Arocior Arocior B Asbestol Chlorextol Clorinol Clorphen Diachlor Dykanol Elemex Eucarel Hyvol Inerteen No-Flamol Puralene 53

Pydraul Pyranol Pyrocior Saf-T-Kuhl Santothem Therminol

If these names appear on the nameplate, the equipment probably contains PCBs and appropriate work practices should be started to prevent exposure. If no nameplate can be found or there is no information to indicate the type of dielectric fluid in it, the EPA states that the equipment should be considered to contain PCBs unless proven otherwise. In general, the EPA states that there is no hard and fast rule to determine if a piece of electrical equipment contains PCBs, short of a laboratory analysis. As a precaution, all transformer oil may be analyzed, as it is possible a transformer that was filled at the factory with non-PCB oil was later filled with PCB oil. A determination may be made during the pre-bid job survey that certain pieces of equipment are exempt from the current demolition job. If an employee is unsure whether a piece of equipment is exempt or not, a site supervisor should be consulted before any action is taken with the equipment in question. The disposal regulations for PCB equipment and dielectric fluid are covered under TSCA. Violation of these regulations carries a criminal penalty. PCB-containing equipment can be disposed of in several ways: incineration, internment at an approved chemical waste landfill or chemical destruction. All require special skills and permits. Site supervisors will communicate to workers what the fate is of PCB-containing equipment. If there are questions, these should be directed to the site supervisor immediately. Disposal procedures for transformers as all follows: 1. If laboratory analysis of a sample of the dielectric fluid shows a PCB concentration in excess of 500 parts per million (ppm), the transformer and the dielectric fluid can be burned together in a high temperature incinerator approved by the EPA, or the liquid can be drained out of the transformer first. If the liquid is drained, the transformer must be flushed with solvent for 18 hours; the solvent and the dielectric fluid must then be disposed of in an EPA-approved high temperature incinerator. After it is resealed, the drained transformer must be disposed of in an EPAapproved chemical landfill. 2. If the transformer is a PCB-contaminated unit containing between 50 and 500 ppm PCBs, the transformer and the liquid can also be incinerated or the dielectric liquid can first be drained. If the liquid is drained, it can be disposed of in a high temperature incinerator, an EPA-approved chemical landfill, or in a high efficiency boiler. 3. The EPA has recently approved a chemical destruction technique that uses chemical reagents to strip chlorine from the PCBs, causing the substance to break down into environmentally safe residues and allowing


the transformer to be reused. This process is mobile and can be brought to demolition job sites. 7.2.4 Preventing Occupational Exposure

Demolition workers can face occupational exposure to PCBs if they attempt to drain a transformer in preparation for salvage. The current practice used by the electrical equipment salvage industry is to transport the transformer or capacitor from the demolition job site to a processing plant capable of safely handling PCBs. These processing facilities are required to use EPA-approved procedures and equipment to handle the hazardous material. Exposure to PCBs is also possible from leaks or spills from old or damaged transformers. Under TSCA, PCB spills have to be reported to the EPA whenever the incident poses a substantial risk to human health or the environment. ,,Substantial risk has not been defined. Any spill should be reported to a site manager or other management personnel. The manager(s) will then determine how and if the EPA or other agencies should be notified. If a spill does occur, the following steps should be taken immediately: All non-essential workers need to be evacuated from the leak or spill area. The area or the leak or spill needs to be adequately ventilated to prevent the accumulation of vapors. If the PCBs are in the liquid form, they need to be collected for reclamation or sorbed in vermiculite, dry sand, earth or similar non-reactive material. Personnel entering the spill or leak area need to wear appropriate personal protective equipment (PPE), including respirators. Only personnel trained in emergency procedures and protected against the hazards, should shut off sources of PCBs, clean up spills or repair leaks. If liquid or solid PCBs are splashed or spilled on an employee, the contaminated clothing needs to be removed promptly and the skin washed thoroughly with soap and water for at least 15 minutes. As stated above, PCB spills must be reported to the site supervisor or other management personnel immediately. The spill may then be reported to the National Response Center operated by the U.S. Coast Guard at (800) 424-8802. The Center will


direct the report to the appropriate EPA environmental emergency office, which will evaluate the extent of the problem and determine what appropriate spill control and cleanup measures should be taken. Cleanup entails the removal of the contaminated soil or debris that shall be placed in special U.S. DOT specified 55-gallon drums. The EPA will provide advice concerning the appropriate disposal site for these drums. In some cases, more complex techniques such as the use of special sorbents or filtration/carbon absorption-type systems may be required. Large spills should be cleaned up by trained personnel. Commercial firms that specialize in spill cleanup or hazardous material management on a contract basis can be contacted to deal with PCB spills. These firms may be able to make recommendations concerning the procedures for contaminated soil and debris. 7.2.5 Protective Practices for Workers In order to safeguard workers against occupational exposure to PCBs, there are a number of steps that can be taken besides the ones already outlined above and common sense. If it is determined that there are PCB transformers and capacitators at a job site, all workers who could be exposed will be informed of the hazards, relevant symptoms, and effects of overexposure to PCBs. Workers will be informed of the exact areas of possible exposure and advised to avoid them unless authorized to work in them. Warning placards or signs will be affixed in readily visible locations in or near PCB work areas. Any equipment determined to contain PCBs, will have labels affixed in a readily visible location. Medical surveillance will be made available to all employees subject to occupational exposure to PCBs. Staton will maintain pertinent medical records of those employees who were exposed to PCBs for the period of employment plus 30 years. In operations where workers may come into direct contact with PCBs, such as preparing a large transformer for transport or draining its dielectric fluid to ready it for salvage, disposable protective clothing impervious to PCBs must be worn. Boot covers, face shields, and gloves should be worn. All clothing should be disposed of in an approved drum. If PCBs get into the eyes, they should be irrigated immediately with large quantities of water and the workers eyes should be examined by a doctor. Adequate ventilation should be maintained in all PCB work areas. This is especially important when PCB transformers or capacitors are located in confined or enclosed areas or underground. Where possible, local exhaust ventilation systems should be used. When engineering controls prove impractical, which may often be the case in demolition, compliance with the permissible exposure limit may be achieved by the use of respirators. When the concentration of PCBs is greater than 1.0 µg/cu m or there is an emergency (entry into area of unknown concentration), there are two types of respirators that can be used. They are the following: 1. Self-contained breathing apparatus with facepiece operated in pressuredemand or other positive pressure mode.


2. Combination Type C supplied-air respirator with full facepiece operated in pressure-demand or other positive pressure mode and an auxiliary selfcontained breathing apparatus operated in pressure-demand or other positive pressure mode. Workers should also wash their hands and any exposed skin before eating, drinking, smoking or using the bathroom. Similarly, no food, drink, or smoking materials are permitted in any area where PCBs are stored, handled or processed. The development of regulations and procedures to deal with the problem of PCBs is an ongoing process. Help is available to deal with these regulations from the EPA regional offices as well as the EPAs Office of Pollution, Prevention and Toxics. 7.3 Avoiding Overexposure to Lead (29 CFR 1926.62)

It has been know for some time that lead has toxic effects on human beings. This knowledge of lead and its toxicity became more evident in the 20th century. This created worldwide alarm that something should be done to reduce leads effects on humans. In 1971, the U.S. passed the Lead-Based Paint Poisoning Prevention Act (LBPPPA). Next, the Resource Conservation and Recovery Act (RCRA) was enacted in 1976 and was amended/reauthorized in 1984 as the Hazardous Solid Waste Amendments (HSWA). Finally, Federal OSHA enacted its regulation of lead in 1993. 7.3.1 Uses of Lead Lead was first used in plumbing. Because it is durable, does not corrode easily, expands, does not crack and is malleable, lead has been an attractive metal to use for plumbing. Gutters, spouts, flashings, and ornamental cornices or moldings were among household items that contained lead. Certain pesticides also contain lead. Lead was, and still is, found in lead alloys, brass and bronze in the shape of faucets, fittings, fixtures, valves and water meters. Demolition workers could also encounter lead in building paints, batteries, cable coverings, ammunition, and caulking. The public is also exposed to lead from certain types of mining and ore processing where there are smelters. The two principal locations where workers commonly encounter lead are in paint that is on structural steel and/or the wood portions throughout any jobsite. However, lead can really be found anywhere on a jobsite. There are two methods in which lead can be detected: 57

1. Through reading as-builts, plans or proprietary specifications for the inclusion of lead-based paint. If the building was built before 1978, the cutoff date established by the Department of Housing and Urban Development, the paint should be tested for lead content. If testing is not done, the work should proceed as if the paint was known to have lead in it. 2. Laboratory analysis by using accepted protocols. 7.3.2 Potential Health Effects of Exposure to Lead (29 CFR 1926.62,

Appendices A and C)

Lead is toxic to the body whenever it is present. Experts agree that children are the most vulnerable to lead. Lead accumulates in the bodys vital organs: skin, eyes, central nervous system, liver, kidneys, blood and the reproductive system. Inhalation and ingestion are the main routes of exposure for lead. The effects of lead can be either acute or chronic. Acute means immediate effects usually due to a large exposure over a shot time period. Chronic means latent effects usually due to a constant exposure over a longer time period. Lead inhalation occurs when lead dust or fumes are released into the air and inhaled. Work practices such as sand blasting or grinding, torch cutting, or painting with lead-based paints can all lead to exposure. When inhaled, the smaller lead particles can travel down the windpipe into the lungs. These smaller particles can move from the lungs into the bloodstream where they can move through the body to be deposited in the major organs, fatty tissue and bones. The larger lead particles can become trapped in the mucus membranes of the nose and throat and later may be swallowed, entering the digestive system. This lead can now enter the stomach and eventually the intestines where it can be absorbed directly into the bloodstream. Ingestion may also occur when lead enters the mouth by eating food, drinking fluids, or smoking cigarettes using ones hands that have become contaminated on the jobsite with lead particles. Children 6 years old or younger retain and absorb more ingested lead than adults. This is due to the fact that children are still in the primary developing stages of life. 70% of absorbed lead is stored in the bones of children. For this reason, workers who have children or grandchildren at home must take special precautions to make their clothes and skin are free from lead before going home. There are documented cases where children have become ill from lead-poisoning due to exposure from a family members clothes and skin from a work site. A worker can be affected by lead months or years after initial exposure as lead is released from the body very slowly. It takes approximately: 25 days for ½ of the lead in blood to leave the body; 25 years for ½ of the lead in many organs to leave the body; and 25 years for ½ of the lead in the marrow of bones to leave the body.

7.3.3 Applicable Government Regulations


The U.S. Department of Labors Occupational Safety and Health Administration has established standards to protect workers from overexposure to lead. OSHAs Lead-inConstruction rule, contained in 29 CFR 1926.62, regulates work practices and procedures which must be followed when working around lead. The EPA regulates the protection of the environment of lead through the proper characterization and disposal of lead waste streams. 7.3.4 Planning A determination must be made if lead is present at job site. OSHAs Lead-inConstruction rule applies to all construction activities where lead or lead-containing materials (LCM) are present. These could include most demolition or salvage operations, removal or encapsulation of lead-based paint, renovations or any structures, cleanup of lead from industrial or commercial processes, and handling, transportation and disposal of LCM from construction locations. The accepted method for determining lead presence is Atomic Absorption Spectrometry. This method is currently the most cost effective for bulk and air sampling. There area also a number of quick test chemical methods that involve applying chemicals to a test area, which change color to reveal the presence of lead. OSHA maintains that exposure to workers to any amount of lead is considered a hazard until exposure monitoring dictates that their exposure is below the permissible level. If a material on a demolition site has any amount of lead, it must be shown that the worker is not being exposed above the PEL. 7.3.5 OSHA Exposure Limits (29 CFR 1926.62 (b)) Federal OSHA has two limits which are important to the demolition industry. The Action Level (AL) and the Permissible Exposure Limit (PEL). The AL is 30 micrograms of lead per cubic meter of air (µg/m3) calculated as an 8-hour TWA. If a workers exposure exceeds the AL, certain provisions in the standard are ,,triggered and specific precautions, included in the rule, must be followed. The PEL is 50 micrograms of lead per cubic meter of air (µg/m 3) calculated as an 8-hour TWA. No worker is allowed to exceed the PEL of 50 µg/m3 averaged over an 8-hour day without adequate control measures being in place. If a worker works longer than an 8hour shift, the PEL must be adjusted by dividing 400 by the number of hours worked. For example, if a worker works for 10 hours, one must divide 400 by 10. The answer to this is 40; thus, the PEL for that day has now dropped from 50 µg/m 3 to 40 µg/m3. 7.3.6 Exposure Monitoring and Assessment (29 CFR 1926.62 (d)) Exposure monitoring, also referred to as air sampling, is used to determine the amount of airborne lead that a worker is exposed to in a given work area. The results of an exposure assessment can determine if a worker is exposed to lead at/or above the AL. OSHA mandates special protective measures that may need to be instituted if levels are 59

at/or above the AL or PEL. The following are general guidelines for the use of certain types of respirators with possible lead exposure: Airborne Concentration of Lead or Conditions of Use Not in excess of 500 µg/m3 (10 x PEL) Not in excess of 1250 µg/m3 (25 x PEL) Not in excess of 2500 µg/m3 (50 x PEL) Required Respirator Half-face air-purifying respirator, other than a disposable respirator, equipped with high efficiency filters. Loose fitting hood or helmet powered airpurifying respirator with high efficiency filters. Full facepiece, air-purifying respirator equipped with high efficiency filters. Tight fitting powered air-purifying respirator with high efficiency filters. ½ mask supplied air respirator operated in pressure demand or other positivepressure mode. Full facepiece supplied air respirator operated in pressure demand of other positive-pressure mode. Full face SCBA operated in pressure demand or other positive-pressure mode.

Not in excess of 50,000 µg/m3 (1000 x PEL) Not in excess of 100,000 µg/m3 (2000 x PEL) Greater than 100,000 µg/m3, unknown concentration, or fire fighting

The following tasks have specific, anticipated exposure levels as well as mandated respirator protection requirements: During manual demolition of painted surfaces, sanding, heat gun applications, and power tool cleaning with dust collection systems, as well as spraying leadbased paint, it should be assumed that the exposure level will be in excess of 50 µg/m3. Using lead-containing mortar, lead burning, rivet busting, power tool cleaning without dust collection systems, clean up activities where dry expendable abrasives are used, and abrasive blasting enclosure movement and removal, it should be assumed that the exposure level will be in excess of 500 µg/m3. Abrasive blasting, welding, cutting, and torch burning, it should be assumed that the exposure level will be in excess of 2500 µg/m 3. It should be noted that in addition, to appropriate respiratory protection, appropriate PPE, hand-washing and training must be utilized with work involving lead. If laboratory testing and personal monitoring indicate that no lead is present or it is above the AL at a specific job site, a record will be made of this finding. This is called a Negative Initial Determination. After this, there is no need for any further monitoring or testing, unless there are changes in equipment, process, control personnel or task where additional workers may be exposed to lead at or above the AL. If the initial exposure assessment reveals exposures to lead, the following should be done:


At/or above the AL but at/or less than the PEL, exposure monitoring must be conducted every 6 months. At/or above the PEL, exposure monitoring must be conducted quarterly. Quarterly and semi-annual monitoring must be continued daily until two consecutive results taken 7 days apart, yield either less than the PEL for the quarterly monitoring or less than the AL for the semi-annual monitoring. 7.3.7 Methods of Compliance If it is determined that workers exposure levels exceed the PEL, engineering, work practice and administrative controls will be implemented to reduce or eliminate the exposure. Respiratory protection may be used in conjunction with these measures. Engineering Controls An engineering control is the modification of a process or the use of specific equipment to reduce or eliminate the exposure. A good example of this might be using a longhandled cutting torch instead of a standard torch to increase the distance between the lead exposure source and the workers breathing zone. Other engineering controls for lead might include: The use of exhaust ventilation which involves a portable local exhaust ventilation system that pulls dust and fumes from the immediate work zone. HEPA vacuum shrouded power tools for removal of paint from work surfaces. Isolation of the work zone by building barricades and limiting access to a potential exposure area. Erecting a sealed negative pressure enclosure around a work zone. The removal of lead-containing material within 4 inches of an area prior to cutting, burning or welding. The use of hydraulic shears to ,,cold cut steel that is painted with leadbased paint. Work Practice Controls Work practice controls are procedures that are used in order to minimize or eliminate exposures to lead. A combination of all of any one of these can be used in effectively reducing exposures to lead. These include: The use of wet removal methods The use of centrifugal, wet, or vacuum blasting The use of heat guns and scraping The use of chemical stripping The use of needle guns The use of HEPA vacuuming


The use of roto peeners Prohibiting any dry sweeping or blowdown with compressed air Administrative Controls Administrative controls involve management changes to reduce or eliminate exposure to workers. This may include the number of hours an employee works at a task or worker rotation as a means of controlling the amount of lead to which an employee is exposed. These controls should be documented in writing and be available to OSHA and other government agencies. These controls should be reviewed and updated at least every 6 months. 7.3.8 Protective Practices for Workers When engineering, work practices, and administrative controls are not enough to reduce lead levels below the PEL, personal protective equipment, including respiratory protection must be used. Respiratory Protection (29 CFR 1926.62 (f) and 29 CFR 1910.134) Respiratory protection is required when employee exposure cannot be controlled below the PEL. Respiratory protection should be used: Whenever the exposure is, or is suspected to be above the PEL Whenever engineering controls, work practices, and administrative controls fail to reduce employee exposure below the PEL Whenever a worker requests respiratory protection As interim protection during exposure assessment according to the task being performed Use and maintenance of respiratory protection will be documented in writing. It is also important to note that the air humans normally breathe contains approximately 21% oxygen and if the oxygen content of air is less than 19.5%, there is an oxygen-deficient environment. If oxygen content is greater than 23.5%, there is an oxygen-enriched environment. Respirators must be chosen for the specific job location, physical limitations of the worker and the performance limitations of the respirator being considered. PPE (29 CFR 1926.62 (g)) Protective work clothing and equipment may be required in certain work situations where lead is present. Some of these are: When the employee is exposed above the PEL When the employee is working with lead compounds that are eye or skin irritants such as lead arsenate As interim protection during exposure assessment


Clean protective garments should be changed weekly; daily if the exposure levels exceed 200 µg/m3. They should be removed in separate changing areas at the end of the shift. Hygiene Practices and Facilities (29 CFR 1926.62(l))

One of the most significant preventive measures that workers can use to avoid lead poisoning is to maintain good personal hygiene practices. Workers should not eat, drink, apply cosmetics, or smoke in areas where lead may be present. Workers should take steps to change clothes and shower if possible before going home if they have been exposed to lead. Lead Warning Signs Employees must abide by posted signs advising of the presence of lead. Employees are also expected to abide by verbal directions given by site supervisors regarding the presence of lead in particular work areas. Hazardous Communication/Material Safety Data Sheet (MSDS)

(29CFR 1926.59/29 CFR 1910.1200)

MSDS are available and can be reviewed by workers prior to the work shift at the job site. MSDS will be reviewed before the start of a shift regarding lead and stressed during toolbox safety meetings on lead.


Chapter 8 Welding


Torch Cutting

Torch cutting involves the generation of temperatures at which metals melt. Proper precautions must be taken to protect workers from heat, intense light rays and the gases and fumes that are generated. Fire prevention procedures must be carried out for the protection of workers and property. When practical, combustibles in the vicinity of the torch cutting should be moved to a safe place. If the piece being worked on and the combustibles cannot be separated by moving one or the other, then suitable barriers such as screens or tarps should be placed to separate the two. In areas where the floors, walls, or ground cover are combustible, these areas should be protected by spraying them with water, spreading damp sand, laying sheet metal, or by equivalent protection. Adequate precautions should be taken near floor and wall openings where people and combustibles are hidden from view. In cases where a serious fire might quickly develop, a fire watch should be assigned to the area. Fire extinguishing equipment should be readily available and all employees trained in its use. The fire watch should be kept in place for a period of time after torch cutting, due to the possibility of smoldering materials which could later ignite. When torch cutting, the use of flammable fuel gases and oxygen poses additional fire hazards. Pure oxygen is extremely dangerous; it can ignite oil or grease and even explode without a flame or spark. Therefore, oxygen regulators and fittings should never be oiled, greased, or cleaned with oily rags. Oxygen should never be used as a substitute for compressed air. If should not be used in pneumatic tools, in oil preheating burners, to start internal combustion engines, to blow out pipelines, to dust clothing to create pressure, or used for ventilation. Fuel gases can be just as dangerous as oxygen. At pressures above 15 psig, or in certain mixture with oxygen, acetylene can spontaneously explode. 65

In addition to fire and explosion hazards, cutters may also be exposed to health hazards in the form of intense light rays and toxic fumes. The intense flame at the tip of the torch emits light rays of three types: visible, infrared, and ultraviolet. Infrared light rays produce erythema (sunburn) on exposed skin surfaces. Intense ultraviolet rays can cause ,,welders flash, a burn to the eyes. To prevent this, goggles or safety glasses with impact-resistant tinted glass filters should be worn during torch cutting. Tinted lenses drastically reduce visibility and should only be worn while actually torch cutting. Face shields are required when there is a chance that slag will splash in the workers face. To eliminate skin damage, worker should wear proper protective clothing. Synthetic fabrics should not e worn because they can melt when struck by hot slag. Cuffs and open pockets can catch burning metal and should be avoided. Flameresistant gloves and safety shoes should always be worn while torch cutting. Clothes should be kept free from oil and grease because they present a fire hazard both from sparks and from potential oxygen leaks. Hazardous fumes and gases can be released into the air as seen in the table below. Some of these are released regardless of the material being cut; others depend on the type of metal or its coating. The two hazards considered most dangerous are torch cutting through lead-based paint and torch cutting in the presence of degreasers. Torch cutting materials, which have been cleaned with a degreaser or even in the vicinity of a degreasing operation, can produce deadly phosgene gas. Adequate ventilation should be ensured before starting any flame-cutting job. Source Cutting Cutting and Welding Welding Rods Chrome-coated fixtures Cadmium Lead Pipe Zinc Any material painted with lead-based paint Any material which contains or has been cleaned with degreasers Chemical Produced Carbon Monoxide Ozone Fluorides Chromates Cadmium Lead Oxide Zinc Oxide Lead Oxide Hydrochloric Acid Phosgene Gas

Torch cutting in enclosed spaces such as in tanks, tunnels, or small closed rooms, demand particular attention to worker safety. A hazardous situation can develop because gases or toxic fumes can easily replace oxygen. Mechanical ventilation such as a fume eductor (an exhaust fan attached to a hose located near the torch cutting operation) should be used whenever possible. If adequate mechanical ventilation cannot be provided, workers should be equipped with supplied-air respirators and a lifeline that is constantly watched by an outside observer. Complete confined space entry safety procedures can be reviewed in Chapter 11 of this manual.


Cylinders should be kept outside the enclosed space, and gases should be shut off at the cylinder when work stops for more than a few minutes. A leaky hose or fitting in an enclosed space can easily result in an explosive and/or oxygen-deficient atmosphere. Torch cutting on containers that have held combustible materials including their residual fumes and dusts can result in fire or explosion hazards. It is important that a rigorous cleaning process be undertaken and that instructions for cleaning be rigidly followed. Containers which have held any of the following materials are considered dangerous, and hot work must not be stated before they are properly cleaned: Flammable liquids including gasoline, kerosene, solvents, or light oils Acids which react with metal and produce explosive hydrogen gas Heavy oils, tars or solids which release combustible gases when exposed to heat Finely divided particles of combustible solids that may form an explosive dust A general rule is that any container, which has held combustibles, should be considered unsafe until proven otherwise by a competent person 8.1 Safe Use of Cutting Torches (29 CFR 1926.350, 1926.352-1926.354) Pressurized cylinders must never be dropped, dragged, or struck in any way. Pry bars and hammers must never be used on any part of the cutting torch system. Cylinders must always be kept in an upright position and secured. When cylinders are transported or moved at the job site while connected for use, the cylinder valves must be closed and the cylinders secured in place. Valve protection caps should be in place when cylinders are not connected for use. When cylinders are hoisted by crane, they should be secured to an approved cradle or platform. Cylinders should never be lifted by their valve protection caps or with electromagnets. Separate areas should be set aside for the storage of fuel gas and oxygen cylinders. These areas should be at least 20 feet apart, or be separated by a 5 foot high, 1 hour fired rated wall, outside the range of falling debris, and away from heavy traffic areas. Storage areas must be kept clear of combustibles, including fuels, and be designated as "No Smoking" areas. Cylinders must not be placed where they might become part of an electrical circuit such as near radiators and piping systems that may be used for grounding electrical equipment. Empty cylinders should be treated the same as full cylinders. Empty cylinders should be stored in a designated area after the following procedures have been completed: Cylinder mark ,,EMPTY or ,,MT Valve closed Valve protection cap replaced Cylinder secured


Setting up a cutting torch requires careful attention to detailed procedures. Only properly trained workers should set up this equipment. The following steps should be taken when setting up a cutting torch: 1. After removing the valve protection cap, the worker must stand to the side of the cylinder valve opening and ,,crack the valve. ,,Cracking refers to quickly opening and closing the valve to remove dust particles from the opening. Cracking should not be done near other welding, cutting or other sources. 2. The regulator must be attached according to the procedure outlined by the manufacturer. Pressure regulators must be serviced and tested for accuracy on a regular basis. It is important that regulators are used only for those gases listed on the regulator. Oxygen and fuel gas fittings are equipped with right and left hand threads to prevent accidental switching. 3. Once the regulators are in place, the hoses (red for fuel, green for oxygen) should be connected and the torch attached. Fittings should not be forced. Any sign of wear means a hose should be repaired or replaced at once. Friction tape can be used to bind the hose together, but no more than 4 out of 12 inches of hose shall be taped. Hoses which are kept neatly coiled are less likely to become kinked, tangled or get run over. Leak Test A leak test may be performed to assure that fittings and valves are correctly seated. The test involves pressurizing the lines and applying soapy water on each fitting and valve. Leaks, which show up as bubbles should be repaired. If, when the valve on a fuel gas cylinder is opened, there is a leak around the valve stem, the valve needs to be closed and the gland nut tightened. If this action does not stop the leak, the use of the cylinder needs to be discontinued, and it needs to be properly tagged and removed from the work area. If the fuel gas leaks from the cylinder valve and cannot be shut off, the cylinder needs to be tagged and removed from the work area. If a regulator attached to a cylinder valve will effectively stop a leak through the valve seat, the cylinder may still be sued. If a leak develops at a fuse plug or other safety device, the cylinder needs to be removed from the work area. Set-Up Procedures The correct procedure for opening valves and lighting a cutting torch is as follows: 1. Prior to opening either cylinder valve, the regulator adjusting valves should be closed. 2. The fuel gas cylinder should be opened between ¾ and one turn. If a detachable wench is required to open the valve, the wrench must be left in place whenever the valve is open. That way, the fuel gas can be shut off quickly in an emergency. 3. Standing away from the face of the regulator, the operator should open the oxygen cylinder valve all the way. This prevents leakage around the valve stem.


4. The working pressures on the regulators should be adjusted. After moving away from the cylinders, the operator should open the fuel valve on the torch ¼ turn, and light the torch with a friction lighter. Serious injury can result from lighting torches with matches or cigarette lighters. 5. The oxygen valve on the torch is then adjusted to set the flame. 6. Caution: A squealing sound means that gases have flashed back into the torch. This fire could burn back into the hoses. Torch valves and cylinder valves must be quickly closed, and the cause of the flashback remedied before relighting the torch. Common causes of flashback are: improper pressures, kinked hoses, and loose, clogged, or overheated tips. Antiflashback devices installed between the torch and the torch hose can prevent flashbacks.

Shut-down Procedures During short breaks, only the torch valves need to be shut down. When the workers leave the area, cylinder valves should be shut off as well. At the end of the shift, the following shut-down procedures should be followed: 1. 2. 3. 4. 5. Torch valves should be closed, fuel gas first. Cylinder valves should be closed next, fuel gas cylinders first. The torch valves should be opened and then closed to relieve pressure. The regulators, hoses, and torch should be removed and stored properly. Valve protection caps should be replaced on the cylinders.


Chapter 9 Safe use of hand tools


Safe Use of Hand Tools

9.1 General Hand Tool Safety (29 CFR 1926.300) Common hand tool injuries are often caused by the workers attitude that ,,anyone knows how to use the tools. The record, however, proves that this is certainly not the case. A survey of injuries in the demolition industry demonstrated that a high percentage of all work-related injuries involve hand tools, including the carrying, using, and storing of such tools. Safe carrying of a hand tool requires taking precautions against injury in the event that a worker slips, trips, or falls. Pointed tools, such as chisels and screwdrivers, should never be carried point-up in any pocket, nor should they be carried point-down in a front pocket. Instead, they should be either hand-carried, with the point or sharp edge held AWAY from the body, or carried in a tool box, tool pouch, or special tool belt. Tools should never be carried in a way that interferes with a workers ability to use both hands while climbing a ladder or structure. Rather, tools should be raised or lowered by rope (in a bucket, if necessary) before or after climbing the ladder. Tools should not be lowered or raised by their electrical cords or air hoses, nor should they be dropped or thrown from one worker to another. Instead, tools should be handed from one worker to another carefully. This not only prevents injuries, but conserves the companys resources by not damaging or breaking expensive tools. 9.2 Hand Tool Safety Strategies Most accidents with hand tools are caused by failure to observe one of the following four rules: 1. 2. 3. 4. Select the right tool for the job. Keep tools in good condition. Use tools in a safe manner. Keep tools in a safe place at all times.

Accidents can be prevented by following these rules and ensuring that all workers have been properly trained in the appropriate use of hand tools, inspecting all tools routinely, and each employee taking responsibility for the proper use and care of tools. It is each employees responsibility to direct questions about hand tools or their use to the site


supervisor before using them. In addition, each employee is responsible for reporting any damage to or defectiveness of hand tools to the site supervisor immediately.

9.3 Hand Tools (29 CFR 1926.301) Prior to using a hand tool, a worker should be familiar with its proper applications, its limitations, and the hazards involved in its use. The tool should be inspected and replaced or repaired at once if found to be defective. The work area should be checked to determine the location of electrical wires, air hoses, or any other potential hazards so they can be removed, guarded or avoided. PPE devices may be required in some situations. When the worker has made sure that his/her footing is secure and that he/she has alerted all other workers who may be endangered by his/her activities, he/she is ready to safely use his/her hand tool. Knives Knives cause more disabling injuries than any other hand tool. Knives should be kept sharp to avoid the excessive use of force. Knives should be used and carried with the blade away from the body whenever possible. Knives should not be used as screwdrivers, pry bars, or picks because they can break, resulting in injury. Sheath knives should never be carried on the front of the belt; instead they should be carried in back, over the hip. Cutters Cutters are frequently used to remove wires, cables, bolts, and reinforcing rods. Eye protection should be worn when working with any cutter. Care should be exercised in the vicinity of live electrical wires. Proper use of cutters involves selecting the right cutter for the job and following the manufacturers capacity rating. Cutters that are too small for a job should never be ,,rocked to facilitate the cutting as this chips the cutters edges. Cutters should never be used as pry bars or nail pullers; this ruins the knives and causes them to get out of alignment. Cutters should also have non-conductive insulated grips. No wiring should be cut until the power has been disconnected. Axes


Axes should be carried with their sheaths or guards in place or at ones side with the handle up and shank in the palm of the hand. Because of the hazard presented by a sharp cutting edge making a wide arc at high speeds, extreme caution must exercised while using an axe. Before lifting an axe, the worker should ensure that no other workers are within range and make sure that any wires, vines, pipes or overhead projections are removed. Next, the axe should be checked to make sure the head is securely attached to the handle, that the handle is free from cracks and splinters, and that the blade is sufficiently sharp for the job. An axe that is dull or too light for the job will bounce off the work, presenting an added hazard. Sledges and Hammers

Sledges and hammers are dangerous implements when their heads chip or come loose from their handles. Hammerheads are made of hard, brittle steel, and flying chips are responsible for large numbers of eye injuries each year. Hammer chipping can be reduced by observing these rules: Replace a hammerhead that is beginning to mushroom. Swing only as hard as is necessary and safe. Hit the target straight on, never at an angle. A hammer should never be used to pound on another hammer. Hammerheads flying off handles can be eliminated by diligent inspection of handles for cracks, splinters and looseness. Chisels

The safe use of chisels begins with the selection of a sharp instrument that is the right size for the job and a hammer of appropriate weight. Chisel heads that have begun to mushroom should be ground to avoid the danger of flying chips, and goggles should always be worn when chisels are in use. Files

Files are harder and more brittle than hammerheads and thus are more prone to chipping. A file should never be cleaned by striking it against a metal object. A file should never be used as a pry bar or a chisel.


Nail Puller A nail puller is a tool specifically designed for the safe removal of nails. Claw hammers whole handles are not built for continuous prying should not be used as nail pullers.


A safe crowbar has a point that grips the object to be moved and a heel to act as a fulcrum. Makeshift crowbars, such as a piece of pipe or iron bar, should be avoided. They are more likely to slip or break and cause injury. Screwdrivers

An object should never be held in the pal of the hand while using a screwdriver on it. The part to be worked on should always be laid on a flat surface or held in a vise. Screwdrivers should not be used as a chisels or icepacks. Shovels Back injuries are the most serious injuries resulting from the use of shovels. To avoid such injuries, proper attention should be paid to the workers stance, his/her lifting technique, and the manner in which he/she turns and empties the shovel. Twisting the spine should be avoided; the legs, rather than the arms, shoulders, and back should be used whenever possible. Workers should use the ball of the foot, rather than the arch to push the shovel. That way, if the foot slips, the sharp corner of the shovel will not cut into the ankle. 9.4 Power Tools (29 CFR 1926.302) Power tools pose extra hazards because workers can experience electric shock, particles in the eyes, burns, cuts, and strains while using power tools. Most hazards can be eliminated by attention to the following rules: Keep power lines and hoses out of passageways. Lines and hoses deteriorate quickly if materials are dropped or driven over. Workers can trip and fall over lines in passageways, presenting the additional danger that the tool may be wrenched out of the operators control.


Keep lines and hoses out of oil and chemicals, away from heat and sharp edges. Disconnect tools from power sources before making repairs or adjustments. Keys should be removed and guards replaced before reconnecting tools to power sources. Before turning on the tool, the area should be checked and potential hazards identified and/or corrected. This permits the operator to concentrate on the work at hand. 9.4.1 Electric Power Tools Electrocution, burns, and shocks can be prevented by observing safe work practices. Only properly grounded or double insulated tools should be used. Additionally, 110 volt, single phase 15-20 amp outlets which are not part of a permanent wiring system are required to have ground fault interrupters or to be incorporated into an assured equipment grounding conductor program. Before each use, electric tools should be inspected for proper grounding, frayed or broken wires, and cracked plugs. All extension cords should also be grounded and ground prongs should never be cut off. Electric tools should not be used when the operator is wet, standing on wet ground or flooring, or in explosive atmospheres. Care should be exercised to avoid cutting through the power supply, a frequent cause of operator injury. 9.4.2 Pneumatic Power Tools Pneumatic power tools present special hazards because their pressurized hoses can be cut, disconnected, or punctured by a careless operator, another worker, falling debris, or from vehicles or equipment running over them. Deterioration from contact with heat or chemical agents or poorly fastened couplings can also cause an air hose to whip. Only approved couplings for the type of hose and working pressure should be used and only with the appropriate coupling safety devices. Air hoses should have a safety device at the source of supply to lower the air pressure in case of hose failure. Hand-held air hammers can become lethal weapons if misused. A tool that is not secured properly can fly out of its retainer with tremendous force and cause serious injury to the operator or to other workers. Pneumatic tools are equipped with deadman switches (automatic shut-off switches) which should never be tied down in the ,,on position. All other tool safety devices should always be engaged properly before the tool is used. To avoid injury from free-flying tools, a good rule is: "Dont squeeze the trigger until the tool is on the work." 9.4.3 Gasoline Power Tools Gasoline-powered tools present hazards association with the use of flammable liquids, as well as dangers from toxic fumes. Remember that gasoline should never be poured


on hot surfaces. It should be kept away from flames or lit cigarettes. Engines should never be fueled while operating. To avoid the deadly build-up of toxic fumes, adequate ventilation should be provided when using gasoline-powered tools in enclosed spaces. When the choice exists, diesel-powered equipment should be used instead of gasoline, as diesel fuel is much less dangerous.

9.4.4 Abrasive Blade Tools When using abrasive or carbide-tipped blades or carbide tools, it is essential that the proper blade is selected for the particular material being worked on. The blade should be mounted tightly, securely, and in the correct rotation direction, according to the manufacturers instructions. When mounting or changing a saw blade, the power supply should be disconnected. Abrasive blades, used for cutting masonry or metal, should be examined for cracks or scratches before each use. A blade guard should always be used and should cover a substantial portion of the blade. The guard should be replaced when it is damaged or worn. When operating an abrasive blade tool, the worker should wear appropriate personal protective equipment and position his/her body to the side of the blade, not directly behind. A full-face shield should always be worn. A back-and-forth-cutting motion should be used. Jamming, grinding and extensive side pressure on the wheel should be avoided. The worker should concentrate on the work surface, making sure the blade does not come into contact with anything other than the material being cut. Abrasive blades should be stored upright in a dry area and proper maintenance procedures followed. 9.4.5 Chainsaws

The chainsaw is one of the most dangerous tools used in demolition. The injuries that result from its misuse are usually quite severe. Serious injuries can result from the kickback reaction that occurs when the nose of the chain comes into contact with a solid object. Many manufacturers have produced anti-kickback mechanisms which, when properly installed, reduce this risk. The device, however, is not a general insurance against accidents and all other safety precautions should be observed. The operator should keep the chain tight, the teeth sharp, and chains that show excessive wear should be discarded. Chains should never be adjusted while the saw is running. The operator should position his/her body entirely to one side of the saw in order to avoid being directly in the kickback path. The operator should never reach above chest height with the saw. A firm grip with both hands is an essential basic


handling precaution. Protective gear, including eye, ear and head protection as well as leather chaps or apron should be worn at all times. 9.4.6 Air Compressors Air compressors are often used by the demolition industry. When misused, however, they can injure and kill. At the source of supply or branch line, there should be a pressure-reducing valve to reduce air pressure in case of hose failure. When attaching air hoses, all the couplings have small openings that line up. A safety clip or wire can inserted to secure the couplings. All pneumatic tools should be secured to the hose or whip by positive means to prevent the tool form becoming accidentally disconnected. Air hoses should be examined before each use for deterioration and for possible clamping of the hose to the fittings. When changing air tools, the valve should be shut off at the source of supply. Under no conditions, should a hose be kinked to stop the airflow. Air hoses should be kept out of aisle ways or areas where they can be damaged by traffic or falling materials. When using compressed air, personal safety equipment is needed. The site supervisor will communicate to employees what is required for a specific job. Cleaning clothes with compressed air is extremely dangerous and is not permitted. Workers must never point or touch the compressed air hose opening to anyones body, ears, or eyes (including the employees own). Injuries with air compressors have included, ear drum damage, eye loss, or injected air bubbles into the blood stream which can be fatal. Compressors should never be operated in confined spaces unless the exhaust is vented to the outside.


Chapter 10 Safe Blasting procedures


Safe Blasting Procedures

The handling and use of explosives are subject to numerous federal, state, and local regulations. These should be consulted before blasting operations begin at any blasting site, especially in an area where Staton has not done previous blasting work. In addition, the manufacturers recommended procedures should be followed through each stage of the blasting operation. Prior to the blasting of any structure or portion thereof, a complete written survey needs to be made by a qualified person of all adjacent improvements and underground utilities. When there is a possibility of excessive vibration due to blasting operations, seismic or vibration tests should be taken to prevent damage to adjacent or nearby buildings, utilities or other properties. The preparation of a structure for demolition by explosives may require the removal of structural columns, beams or other building components. This work should be directed by a structural engineer or a competent person qualified to direct the removal of these structural elements. Extreme caution should be taken during this preparatory work to prevent the weakening and premature collapse of the structure. The use of explosives to demolish smokestacks, silos, or similar structures should only be permitted if there is a minimum of 90 degrees of open space extended for at least


150% of the height of the structure, or if it can be demonstrated that consistent previous performance with tighter constraints at the site. When blasting bridges or their parts is contemplated, care should be taken to prevent the blockage of navigable waters or channels without permission of the proper authorities. 10.1 Fire Precautions

The presence of fire near explosives presents a severe danger. Every effort should be made to ensure that fires or sparks do not occur near explosive materials. Smoking, matches, firearms, open flame lamps, and other fires, flame or heat-producing devices are prohibited in or near explosive magazines or in areas where explosives are being handled, transported or used. Employees working near explosives should not even carry matches, lighters or other sources of sparks or flame. Open fires or flames are prohibited within 50 feet of any explosive materials. In the event of a fire that is in imminent danger of contact with explosives, all employees and any other persons at risk must be removed to a safe area. Only authorized and qualified person is permitted to handle and use explosives. Usually this is a person with greater experience, knowledge and training in the field of explosives. Each employee is responsible for telling a site supervisor if he or she is not qualified to perform a designated task, including blasting duties. Workers, designated as blasters, are required to furnish satisfactory evidence of competency in handling explosives and in safely performing the type of blasting required. A competent person will always be responsible for the explosives and for enforcing all recommended safety precautions in connection with them. 10.2 Use of Explosives (29 CFR 1926.901, 1926.905-1926.914) Protection of the public is an essential element to any blasting operation. Blasting operations should be conducted between sunup and sundown, whenever possible. Adequate signs should alert the public to the hazard presented by blasting. On the other hand, the blast should not be publicized. Blasting mats, berms or other containment should be used where there is a danger of rocks or other debris being thrown into the air or where there are buildings or transportation systems nearby. Care should be taken to make sure mats and other protection do not disturb the connections to electrical detonators or to other initiation systems. Every blasting project is unique and requires its own protective measures. A written diagram of the loading for each blast is required. Radio, television and radar


transmitters create fields of electrical energy that can, under exceptional circumstances, detonate electric blasting caps. Certain precautions must be taken to prevent accidental discharge of electric detonators from current induced by radar, radio transmitters, lighting, adjacent power lines, dust storms, or other sources of extraneous of static electricity. These precautions should include the following: Ensuring that mobile radio transmitters and portable telephones on the job site are de-energized and effectively locked if they are less than 100 feet away from electric detonators in other than original containers. The prominent display of adequate signs warning against the use of mobile radio transmitters on all roads within 1000 feet of the blasting operations. Maintaining the minimum distances recommended by the Institute of the Makers of Explosives in SLP 20, "Safety Guide for the Prevention of Radio Frequency Radiation Hazards in the Use of Commercial Electric Detonators (Blasting Caps)" between the nearest transmitter and electric detonators. The suspension of all blasting operations and removal of persons from the blasting area during the approach and progress of an electrical storm. Firing After loading of the explosives is completed, there should be as little delay as possible before firing. Each blast should be fired under the direct supervision of the blaster, who should inspect all connections before firing and who should personally see that all persons are in the clear before giving the order to fire. Standard signals, which indicate that a blast is about to be fired and a later "all clear" signal, should be adopted. It is important that everyone working in the area be familiar with these signals and that they be strictly obeyed. Inspection After the Blast Immediately after the blast has been fired, the firing line needs to be disconnected from the blasting machine and short-circuited. Where power switches are used, they need to be locked open or in the off position. Sufficient time needs to be allowed for smoke and fumes to leave the blasted area before returning to the shot. An inspection of the area and the surrounding rubble needs to be made by the blaster to determine if all charges have been exploded before employees are allowed to return to the operation. All wires should be traced and the search for unexploded cartridges made by the blaster. 10.3 Non-Explosive Demolition Agents Recent technology has produced alternatives to blasting by explosives. In areas where noise, dust, vibration, and flyrock are problems, splitting of rock or concrete by chemical reaction may be a desirable alternative. In addition to the method described in the following paragraphs, there are a number of non-explosive materials available from various manufacturers. One method to use is the following: after drilling holes in concrete, a lime-based powder is mixed with water to create a slurry-type material. The slurry is then poured into the


holes and after several hours, the material slowly expands to as much as 4300 psi causing the concrete around the holes to fracture. Since the material may bubble while being mixed and during the first 6-8 hours after mixing, eye protection should be worn. Rubber gloves and boots should also be worn as the lime in the mixture can cause dermatitis. Mixing should be done only in straightsided containers.

Chapter 11 Safe Practices for Demolishing special Structures


Safe Practices for Demolishing Special Structures

11.1 Safety When Working in Confined Spaces (29 CFR 1926.21 (b) (6), 1926.352

(g), 1926.353 (b), 1910.146)

Demolition workers often come into contact with confined spaces when demolishing structures at industrial sites. These confined spaces can be generally categorized in two major groups: those with open tops and a depth that restricts the natural movement of air; and enclosed spaces with very limited openings for entry. Examples of these spaces include storage tanks, vessels, degreasers, pits, vaults, casings, silos and utility tunnels.


The hazards encountered when entering and working in confined spaces are capable of causing bodily injury, illness, and death. Accidents occur among workers because of failure to recognize that a confined space is a potential hazard. It should, therefore, be assumed that the most unfavorable situation exists in every case and that the danger of explosion, poisoning, and asphyxiation will be present at the onset of entry. Hazardous atmospheres encountered in confined spaces can be divided into four categories: flammable, toxic, irritant and/or corrosive and asphyxiating. Flammable Atmospheres

A flammable atmosphere generally arises from enriched oxygen atmospheres, vaporization of flammable liquids, by-products of work, chemical reactions, concentrations of combustible dusts and deabsorption of chemicals from inner surfaces of the confined space. Combustible gases or vapors will accumulate when there is inadequate ventilation in a confined space. Flammable gases such as acetylene, butane, propane, hydrogen, methane, and natural or manufactured gases or vapors from liquid hydrocarbons can be trapped in confined spaces. Since many gases are heavier than air, they will seek lower levels such as pits, vaults, and various types of storage tanks and vessels. In a closed top tank, it should also be noted that lighter-than-air gases may rise and develop a flammable concentration if trapped above the opening. The by-products of work procedures can generate flammable or explosive conditions within a confined space. The most common of these activities is welding or cutting in a confined space. Chemical reactions forming flammable atmospheres occur when surfaces are initially exposed to the atmosphere or when chemical combine to form flammable gases. Combustible dust concentrations are usually found during the process of loading, unloading, conveying grain products, nitrated fertilizers, finely ground chemical products and any other combustible material. High charges of static electricity which rapidly accumulate during periods of relatively low humidity (below 50%) can cause certain substances to accumulate electrostatic charges of sufficient energy to produce sparks and ignite a flammable atmosphere. These sparks may also cause explosions when the right ratio of air or oxygen to dust or gas is present. Deabsorption of chemicals from the inner surfaces of a confined space is another process that may produce a flammable atmosphere. For example, after liquid propane is removed from a storage tank, the walls of the vessel may desorb the remaining gas from the porous surface of the confined area.


Toxic Atmospheres

The substances to be regarded as toxic in a confined space can cover the entire spectrum of gases, vapors, and finely-divided airborne dust. The sources of toxic atmospheres encountered may arise from the manufacturing process, the product stored, or operations performed in the confined space. Toxic substances generated during the operations of an industrial facility can remain long after production has ceased at the location. Substances used in the production, cleaning, maintenance, or transport of materials may remain at the site and may need to be dealt with before work can proceed. Toxic material can include: sludges left in pits which are hazardous or carcinogenic; solvents used for cleaning or degreasing; fumes generated by burning previously coated metal surfaces; residual chemicals remaining on floors, ceilings, or walls and toxic gases left in tanks. One of the most hazardous substances a demolition worker may face when working in a confined space is carbon monoxide. Carbon monoxide is a relatively abundant, colorless, odorless gas that has approximately the same density as air. It is particularly dangerous because of its poor warning properties. Early stages of carbon monoxide intoxication are nausea and headache. It can be fatal at high levels and should be specifically tested for in any suspected confined space. Carbon monoxide can be a by-product of incomplete oxidation in welding and cutting operations and can also be generated by the re-circulating of machinery exhaust emission. Carbon monoxide levels can only be prevented by strict ventilation control or the use of special catalytic converters.

Irritant (Corrosive) Atmospheres

Irritant atmospheres vary among all areas of industrial activity. They can be found in plastics, manufacturing plants, chemical plants, the petroleum industry, tanneries, refrigeration industries, paint manufacturing, mining operations, etc.


Prolonged exposure to irritant or corrosive concentrations in a confined space may produce little or no evidence of irritation. This has been interpreted to mean that the worker has become adapted to the harmful agent involved. In reality, it means that, due to the damage of the nerve endings in the mucous membranes of the upper respiratory tract, there has been a general weakening of the defense reflexes from changes in sensitivity. This is dangerous because the worker is usually not aware of any increased exposure to these substances. Asphyxiating Atmospheres The normal atmosphere is composed of approximately 20.9% oxygen, 78.1% nitrogen, and 1% argon with small amounts of various other gases. Reduction of oxygen in a confined space may be the result of either consumption of displacement. The consumption of oxygen takes place during combustion of flammable substances as occurs during welding, heating, cutting and brazing. Oxygen may also be consumed during chemical reactions such as the formation of rust (iron oxide) on the exposed surface of the confined space. The number of people working in a confined space and their level of physical activity will also influence the oxygen consumption rate. A second factor in oxygen deficiency is displacement by another gas. Gases that are used to displace air, and therefore reduce the oxygen level, include helium, argon, and nitrogen. Oxygen deprivation is one form of asphyxiation. While it is desirable to maintain the atmospheric oxygen level at 21% by volume, the body can tolerate some deviation from this ideal. OSHA requires 19.5% oxygen. To be safe, workers should not enter a confined space without supplied air. When the oxygen level falls to 17%, the first sign of oxygen deficiency is the deterioration of night vision, which is not noticeable until normal oxygen concentration is restored. Between 14 to 16%, the physiological effects that accompany oxygen deprivation consist of increased breathing volume, accelerated heartbeat, very poor muscular coordination, rapid fatigue, and intermittent respiration. Between 6 and 10%, the effects are nausea, vomiting, inability to perform, and unconsciousness. At less than 6%, the effects consist of spasmatic breathing, convulsive movements, and death within minutes. 11.1.1 General Safety Hazards In addition to the hazardous atmospheres that a demolition worker may confront when working in confined spaces, there are general hazards that may be encountered as well. These hazards include communication problems, entry and exit, temperature considerations, noise, vibration, and other general physical hazards. Communication Problems


Communication between the worker inside and the standby person outside is of utmost importance. Frequently, the body positions that are assumed in a confined space make it difficult for the standby person to detect an unconscious worker. When visual monitoring of the worker is not possible because of the design of the confined space or location of the entry hatch, a voice or alarm-activated explosion-proof type of communication system may be necessary. Suitable illumination of an approved type is required to provide sufficient visibility for work in accordance with the OSHA requirements. Entry and Exit

Entry and exit time has major significance as a physical limitation and is directly related to the potential hazard of the confined space. The precautions taken, and the standby equipment needed to maintain a safe work are will be determined by the means of access and rescue. The following should be considered: type of confined space to be entered, access to the entrance, number and sizes of openings, barriers within the space, the occupancy load, the time required for exiting in the event of fire or vapor incursion, and the time required to rescue injured workers. Temperature

Temperature ranges within a confined space should be a prime concern for demolition contractors. The air temperature, its velocity or flow, moisture content, and the radiant heat generated by the structure should be reviewed before workers enter a confined space. Supervisors and/or standby workers will closely monitor a workers performance in a confined space. Any change in efficiency should be suspect. All workers should be aware of the possibility of heat exhaustion, heat cramps, or heat stroke in warm environments, and frostbite, trenchfoot, or general hypothermia in cold environments. When planning work in a confined space, it is important to remember that protective insulated clothing for both hot and cold environments will add additional bulk to the worker and are factors which will affect movement in the confined space as well as exit time. Noise Noise problems are usually intensified in confined spaces because the interior tends to cause sound reverberation that exposes the worker to higher sound levels than those found in an open environment. This intensified noise increases the risk of hearing damage to workers that could result in temporary or permanent loss of hearing. Noise in 87

a confined space that may not be intense enough to cause hearing damage may still disrupt verbal communication with the emergency standby person on the exterior of the confined space. If the workers inside are not able to hear commands or danger signals due to excessive noise, the probability of accidents increases. Vibration Whole body vibration may affect multiple body parts and organs depending upon the vibration characteristics. Segmental vibration, unlike whole body vibration, appears to be more localized, creating injury to the fingers and hands of worker using tools such as pneumatic hammers, rotary grinders, or other vibrating hand tools. Vibration in a confined space can cause a generalized stress for a worker and decreases his/her ability to react quickly in an emergency. Proper scheduling, worker supervision, and installation of mufflers on hand tools can eliminate much of the danger associated with vibration. General Physical Hazards There are numerous general physical hazards that may occur when working in a confined space. Some cannot be eliminated because of the nature of the confined space or the work to be performed. These hazards include such items as scaffolding, surface residues, and structural hazards. Surface residues in confined spaces can increase the hazard of electrical shock, reaction of incompatible materials, liberation of toxic substances, and bodily injury due to slips and falls. Without protective clothing, additional hazards to health may arise due to surface residues. Structural hazards within a confined space such as baffles in horizontal tanks, trays in vertical towers, bends in tunnels, overhead structural members, crane suspended man baskets or scaffolding installed for maintenance constitute physical hazards which are aggravated by the physical surroundings. Before work begins, any valves or pipes should be physically disconnected or isolation blanks bolted in place. Because of the chance of carbon monoxide poisoning, internal combustion engines should not be used in confined spaces nor should heaters be used unless they are vented properly.

11.1.2 Safe Work Practices Assuring safety when working in a confined space requires proper planning. Safe work practices for working in confined spaces include: preparation of a rescue plan; the development and use of an entry permit system; testing and monitoring the area; purging, ventilating, and cleaning the space; worker training; proper safety equipment and clothing; and posting of the site. Preparation of a Rescue Plan


Procedures for rescue from confined spaces should be specifically designed for each entry. There should be a trained standby person assigned to that confined space with a fully-charged positive pressure, self-contained breathing apparatus (SCBA) at hand. The additional duties of the standby person include: maintaining unobstructed lifelines, communicating to all workers within the confined space, and summoning rescue personnel, if necessary. Under no circumstances will the standby person enter the confined space until he/she is relieved and is assured that adequate assistance is present. However while awaiting rescue personnel, the standby person may make rescue attempts utilizing the lifelines from outside the confined space. Rescue teams entering a confined space should be equipped with all the aforementioned safety equipment and required lifelines. Permit System In many cases, accidents occur in a confined space because of a lack of proper control. Potentially hazardous atmospheres and general safety hazards can compound the supervisors problems. Proper safety requires that entry into a confined space work area be strictly regulated. Entry into a confined space should be by authorization only. The authorization specifies in writing the location and type of work to be done, certifies that all existing hazards have been evaluated by a qualified person, and ensures that the necessary worker protection measures have been taken. The supervisor or a qualified person should be responsible for the authorization and should sign off when the following area and actions have been reviewed and confirmed: 1. Location and the description of the work to be done 2. Hazards that may be encountered 3. Complete isolation checklist Blanking and/or disconnecting Electrical lockout Mechanical lockout 4. Special clothing and equipment PPE and clothing Safety harness and/or lifelines Tools approved for use Approved electrical equipment 89

5. Atmospheric test readings Oxygen level Flammability and/or explosive levels Toxic substance levels 6. Atmospheric monitoring while work is being performed 7. Personnel training and understanding of the hazards 8. Standby person(s) 9. Emergency procedures and location of first aid equipment The authorization should be posted in a conspicuous place, close to the entrance. A copy should also be one file. Testing and Monitoring Entry into a confined space should be prohibited until initial testing of the atmosphere has been done from the outside. Appropriate tests should be performed to ensure the atmosphere is safe. The tests performed should include those for oxygen content, flammability, and toxic materials. Any necessary additional tests will be selected and performed to the satisfaction of a qualified person. Entry into confined space for any type of hot work should be prohibited when tests indicate the concentration of flammable gases in the atmosphere is greater than 10% of the lower flammability limit (LFL). The lower flammability limit is the minimum concentration of a combustible gas or vapor in the air that will ignite if an ignition source is present. To make necessary corrections in the flammability measurement, it is necessary to determine the oxygen level (by appropriate testing) prior to measuring the range of flammability. Atmospheric monitoring should be performed in accordance with the authorized checklist. Equipment for continuous monitoring of gases and vapors should be explosion-proof and equipped with an audible alarm or danger signaling device that will alert employees when a hazardous condition develops. Instruments used for testing the atmosphere in a confined space should be selected for their functional ability to measure hazardous concentrations. Instruments should be calibrated in accordance with the manufacturers guidelines or manuals. Each calibration should be recorded.

Purging and Ventilating the Confined Space Environmental control within a confined space is accomplished by purging and ventilating. The method used should be determined by the potential hazards that arise due to the product stored or produced, suspected contaminants, work to be performed, and the design of the confined space. When ventilating and/or purging operations are to be performed, the blower controls should be at a safe distance from the confined space. An audible warning device should be installed in all equipment to signal when there is a ventilation failure.


When a ventilation system is operational, airflow measurements should be made before each work shift to ensure that a safe environmental level is maintained. To determine that precautions necessary for purging and ventilating have been taken, initial testing of the atmosphere should be performed from outside the confined space before ventilation begins. Testing of more remote regions within the confined space may be performed once the immediate area within the confined space has been made safe. Exhaust systems should be designed to protect workers in the surrounding area from contaminated air. Where continuous ventilation is not a part of the operating procedure, the atmosphere should be tested until continuous acceptable levels of oxygen and contaminants are maintained for three tests at 5-minute intervals. Care should be taken to prevent recirculating of contaminated air and interaction of airborne contaminants. Continuous general ventilation should be maintained where toxic atmospheres are produced as part of a work procedure such as welding or cutting, or where toxic atmospheres may develop due to the nature of the confined space, as in the case of desorption from walls or evaporation of residual chemicals. General ventilation is an effective procedure for distributing contaminants from a local generating point throughout the workspace to obtain maximum dilution. However, special precautions should be taken if the ventilation system partially blocks the exit opening. These precautions include devising a method for supplying respirable air to each worker for the time necessary for exit and a method of maintaining communications. Local exhaust ventilation should be provided when general ventilation is not effective due to restrictions in the confined space or when high concentrations of contaminants occur in the breathing zone of the worker. Cleaning the Space In some cases, the inside of the structure must be cleaned before dismantling work can begin on a structure with a confined space. The prescribed method is dependent upon the product in the space. If the confined space contains a flammable atmosphere above the upper flammable limit, it should be purged with an inert gas to remove the flammable substances before air ventilation begins. If at all possible, initial cleaning should be done from outside the tank. Special procedures should be adopted to handle the hazards created by the cleaning process itself. For example, if the tank is steamed: 1. It should be allowed to cool prior to entry. 2. Ventilation should be maintained during neutralization procedures in order to prevent build up of toxic materials.


3. Steaming should not be used as a cleaning method when the product stored was a liquid with an auto-ignition temperature 120% or less of the steam temperature. 4. The pipe of nozzle of the steam hose should be bonded to the tank to decrease the generation of static electricity that could accumulate in tanks during steaming procedures. Worker Training Personnel working in the vicinity of confined spaces should be made aware of the hazards association with them. Personnel who are required to work in a confined space, or in support of those working in a confined space, should have additional training or documentation of prior training in the following areas: 1. 2. 3. 4. 5. Emergency entry and exit procedures. Use of applicable respirators. First Aid. Safety equipment use. Rescue and training drills designed to maintain proficiency. These should be done at least annually, or at lesser intervals, if deemed necessary. 6. Permit system. Proper Safety Equipment and Clothing Those items normally used to protect against traumatic injury include: safety glasses, hardhats, footwear, and protective clothing. Additional safety equipment is necessary to protect the worker in a confined space. When ventilation failures allow the build up of toxic or explosive gases within the time necessary to evacuate the area, or when the atmosphere is immediately dangerous to life and health, a safety harness with "D" rings for attaching a lifeline should be worn at all times. The combination of a body harness with lifeline should be used when an employee is required to enter the confined space to complete the gas analysis. Safety belts may be used as the primary means of suspension from the lifeline only when rescue may be made by keeping the disabled body in a position that will maintain easy passage through exit openings. If the exit opening is less than 18 inches (45 cm) in diameter, a wrist type harness should be used. The respiratory protection required when working in a confined space should be determined by a qualified person based on the conditions and test results of the confined space, and the work activity to be performed. The respirators used should be NIOSH approved and should be fitted and maintained in accordance with government regulations.

Posting the Site


All entrances to any confined space should be posted. Signs should include, but not necessarily limited to Danger: Confined Space Entry by Authorization Only. When a specific work practice is performed or specific safety equipment is necessary, the following statement should be added, in large letters, to the warning sign: Respirator Required for Entry, Lifeline Required for Entry, Hot Work Permitted, or No Hot Work. Emergency procedures, including phone numbers of fire departments and emergency medical services, should be posted conspicuously within the immediate area of the confined space or at the telephone from which help would be summoned. 11.2 Safe Practice When Demolishing a Chimney or Stack (29 CFR 1926.854)

When preparing to demolish any chimney or stack, the first step should be a careful, detailed inspection of the structure by an experienced person. If possible, architectural drawings should be consulted. Particular attention should be paid to the condition of the chimney or stack. Workers should be on the lookout for any structural defects such as weak or acid-laden mortar joints and any cracks or openings. The interior brickwork in some sections of industrial chimney shafts can be extremely weak. If a stack has been banded with steel straps, these bands should be removed only as the work progresses from the top down. An experienced person should prepare a plan. This plan should outline the steps to be followed in demolishing the chimney or stack.

11.2.1 Safe Work Practice When hand demolition is required, it should be carried out from a working platform. Experienced personnel should install a self-supporting tubular scaffold around the


chimney. Particular attention should be paid to the design, support and tie in (braces) of the scaffold. It is essential that there be adequate working clearance between the chimney and the work platform. Access to the top of the scaffold should be provided by means of portable walkways. The platforms should be decked solid and the area from the work platform to the wall bridged with a minimum of 2-inch thick lumber. A back rail 42 inches above the platform with a midrail covered with canvas or plywood should be provided. An alternative to the erection of a self-supporting tubular steel scaffold is to ,,climb the structure with a creeping bracket scaffold. Careful inspection of the masonry and a decision as to the safety of this alternative must be made by a competent person. It is essential that the masonry of the chimney be in good enough condition to support the bracket scaffold. The area around the chimney should be roped off or barricaded and secured with appropriate warning signs posted. No authorized entry should be permitted to this area. It is also good practice to keep a safety person on the ground with a form of communication to the workers above. 11.2.2 Debris Clearance If debris is dropped inside the shaft, it can be removed through an opening in the chimney at grade level. The opening at grade must be kept relatively small in order not to weaken the structure. If a larger opening is desired, a professional engineer should be consulted. When removing debris by hand, an overhead canopy of adequate strength should be provided. Workers should not remove debris by hand while demolition work is being performed overhead. If machines are used for removal of debris, proper overhead protection for the operator should be used. Excessive debris should not be allowed to accumulate inside or outside the shaft of the chimney as the excess weight of the debris can impose pressure on the wall of the structure and might cause the shaft to collapse. 11.2.3 Worker Safety When working on the work platform, all personnel should wear hard hats, sleeve shirts, goggles, respirators and full-body safety harnesses with shock-absorbing lanyards, as required. Care should be taken that the proper number of workers are assigned to the task. Too many people on a small work platform can lead to accidents. Special attention should be given to weather conditions when working on a chimney. No work should be done during inclement weather such as during lightning or high wind situations. The worksite should be wetted down, as needed, to control dust. 11.2.4 Demolition by Deliberate Collapse


Another method of demolishing a chimney or stack is by deliberate collapse. This requires extensive planning and experienced personnel and should be used only when conditions are favorable. There must be a clear space for the fall of the structure of at least 45 degrees on each side of the intended fall line and 1½ times the total height of the chimney. Consider vibration may be encountered when the chimney falls, so there should be no sewers or underground services on the line of the fall. Lookouts must be posted on the site, and warning signals must be arranged. The public and other workers at the job site must be kept well back from the fall area. The use of explosives is one way of setting off deliberate collapse. Only qualified persons should undertake this kind of demolition. The entire work area should be cleared of nonessential personnel before any explosives are placed. Though the use of explosives is a convenient method of bringing down a chimney or stack, there may be a considerable amount of vibration produced. 11.3 Demolition of Pre-Stressed Concrete Structures

The various forms of construction used in conventional structures built over the last few decades may create problems when the time comes to demolish them. Pre-stressed concrete structures fall into this general category. The most important aspect of demolishing a pre-stressed concrete structure takes place during the engineering survey. During the engineering survey, a qualified person will determine if the structure to be demolished contains any pre-stressed members. It is important to inspect all available records of the structure and to establish that the construction conforms to these details. If records are not available, a careful visual examination will often show whether a structure is pre-stressed or not. If there is still a doubt as to whether the structure is prestressed, a professional engineer or qualified architect should be consulted. 11.3.1 Recognizing Pre-Stressed Concrete Structures In order to determine if a structure contains any pre-stressed members, a basic understanding of the many applications of pre-stressed members and the technology used in their manufacture is required. When determining whether a particular structure is or is not pre-stressed, the following information ma be helpful: Ages of Construction Almost all pre-stressed structures in this country have been built since 1946.


Span/Depth Ratio Pre-stressed beams and slabs may have a greater span/depth ratio than comparable reinforced concrete beams and slabs. The main beam span is 10.7 m (35 ft) or greater in either direction. Beams are shallow with a thin slab of concrete. Shapes of Sections Pre-stressed units are often formed of shapes other than the simple rectangle--for example, Ts, Us Is and hollow boxes are commonly used. Transverse stiffeners may occur at intervals and contain the additional tendons. When pre-stressed or pre-cast flooring units have been used, it is often found that adjacent units have a different upward camber or uneven soffit. Joints Post-tensioned members made from individual units will have visible joints between each element. The joints often vary in thickness and are formed of cement mortar or concrete. Recently, thin resin joints have also been used. Concrete Strength Ordinary Portland cement with a strength in excess of 7000 PSI may be an indication of pre-stressed concrete but not always. The strength of concrete increases with age. In ordinary reinforced concrete, the tensile weakness is overcome by placing steel reinforcement (re-bar) in the tensile zone. This usually occurs near the bottom of a beam or slab at midspan and at the top, over the supports in continuous members. More recently, pre-stressing has been used to provide pre-compression in these zones. Pre-stressing is achieved by means of steel tendons that are placed in tension and then anchored against the concrete. A force corresponding to an average stress of about 1000 PSI over the whole cross-sectional area of the section is applied. The position of the tendons is varied to give high compression stresses where required in the section. Tendons consist of either single or groups of small diameter strands of high tensile wires or high tensile bars with an overall diameter between 13 millimeters and 40 millimeters (0.512" and 1.57"). The tendons are anchored by means of cones, wedges, or screw heads with locking nuts. Individual wires, strands, and bars may be anchored separately or by groupings. Anchors are usually located at the ends of post-tensioned units and are normally recessed into heavily reinforced solid end blocks. In long spans or continuous members, anchors and/or couplers may occur at intermediate positions. There are two basic methods of pre-stressing concrete members: pre-tensioning and post-tensioning. In pre-tensioning, the steel is tensioned before the concrete is cast, and the pre-stressing force is transferred to the concrete by bond. Pre-tensioning is used primarily for factory-made units. In post-tensioning, the tendons are tensioned after the concrete has been cast and allowed to harden; the pre-stress is sustained by means of end anchors. More generally, however, post-tensioning is applied to pre-cast units or units that are cast in-situ, in which ducts are formed within the members. The tendons


are inserted in these ducts and then stressed and anchored with permanent anchors. In some designs, the tendons are placed outside the shell and protective concrete is added later. 11.3.2 Categories of Pre-Stressed Concrete There are four main categories of pre-stressed members. The category, or categories, should be determined before attempting demolition, bearing in mind that any prestressed structure may contain elements of more than one category. Category 1. Members pre-stressed before the application of the superimposed loads. All cables or tendons are fully bonded to the concrete or grouted within ducts. Category 2. The same as Category 1, but having the tendons left un-grouted/unbonded. This type of construction can sometimes be recognized from the access points that may have been provided for inspection of the cables and anchors. More recently, un-bonded tendons have been used in the construction of beams, slabs, and other members; these tendons are protected by grease and surrounded by plastic sheathing, instead of the usual metal duct. Category 3. Members that are pre-stressed progressively as the building construction proceeds and as the dead load increases, using bonded tendons, the same as Category 1. Category 4. Members that are pre-stressed progressively as the building construction proceeds using un-grouted/un-bonded tendons, the same as Category 2. Examples of construction using members of Categories 3 and 4 are relatively rare, but may be found in the podium of a tall building of some types of bridges. 11.3.3 Hazards of Pre-Stressed Concrete Pre-stressing stores up an enormous amount of energy in the structure. Most of this energy must be released at the first stage of demolition. Sudden failure of the member can occur if handled incorrectly. Approximately 90% of the stored energy of a prestressed member is contained in the tendons. Rapid release of this energy, either by removing the surrounding concrete and/or burning through the high-tensile steel, can cause sudden failure. Pre-stressed members are usually designed to resist the applied load in one direction only and should be handled with this in mind. Multiple tendon members are normally pre-stressed symmetrically and any asymmetrical release of tendons should not be allowed, as the member might buckle sideways. Members that are continuous over more than one support may have tendons the full length of the structure and demolition of one section may release and collapse the


adjoining spans. This is a particular hazard in the case of incompletely grouted members and structures of Category 2, due to the danger of progressive collapse. After the tendons of pre-stressing steel have been anchored, the individual ends are usually cut off. The anchors are encased with protective concrete, and the ducts are usually filled with a cement grout. This performs two function: 1. Protects the pre-stressing steel from corrosion 2. Bonds the tendon to the concrete along the length of the duct It is important to remember that in an increasing number of recent structures, the tendons are not grouted. Other forms of protection are then provided. In some cases, particularly when floor slabs are involved, the tendons are first encased in grease and then enclosed in a plastic sheath. These tendons are classified as un-bonded. The distinction between bonded and un-bonded tendons is of the utmost importance. The behavior of members containing these types of tendons will be different during the demolition process. There is a fundamental distinction as to how rapidly the energy will be released between bonded and un-bonded tendons. If the bonding remains intact, as for example with pre-tensioned strands or with well-bonded post-tensioning tendons over an adequate length, the release will take place incrementally and not explosively. Progressively pre-stressed structures present additional hazards. The construction process cannot be easily reversed for demolition because there is a minimum dead load weight essential for structural stability. Removing this weight may cause premature failure. This type of failure may include upward deflection, secondary collapse of floor or wall panels, or the sudden spontaneous collapse of the entire structure. 11.3.4 Recommended Procedures for Demolition Pre-Tensioned Members: These usually do not have any end anchors, the wires being embedded or bonded within the length of the member. Simple pre-tensioned beams and slabs of spans up to about 7 meters (23") can be demolished in a manner similar to ordinary reinforced concrete. Pre-tensioned beams and slabs may be lifted and lowered to the ground as complete units after the removal of any composite concrete covering the tops and ends of the units. Lifting the structure should be done from points near the ends of the units or from lifting point positions. Reuse of lifting eyes, if in good condition, is recommended whenever possible. When units are too large to be removed, consideration should be given to temporary shoring. Pre-Case Units Stressed Separately from the Main Frames of the Structure: These units have end anchors, and grouted and/or un-grouted ducts. Units of this type should be lowered to the ground if possible. After lowering, the units can be turned on their side, with the ends up on blocks. This may suffice to break the unit and release the pre-stress. If not, a sand bag screen should be erected around the ends, and demolition


can commence, taking care to clear the area of any personnel. The end blocks may be heavily reinforced and difficult to break up. Monolithic Structures: The advice of a professional engineer experienced in pre-stressed work should be sought before any attempt is made to expose the tendons or anchorage of structures in which two or more members have been stressed together. It will usually be necessary for temporary supports to be provided, so the tendons and the anchorage can be cautiously exposed. In these circumstances, it is essential that no indiscriminate attempts to expose and de-stress the tendons and anchorages are made. Progressively Pre-Stressed Structures: In the case of structures of this type, it is essential to obtain the advice of a professional engineer and to demolish the structure in strict accordance with the method statement supplied. The stored energy in this type of structure can be substantial. In some cases, the inherent properties of the stressed section may delay failure for some time, but the presence of these large pre-stressing forces may cause sudden and complete collapse with little or no warning. 11.3.5 Job Site Safety All workers will be informed of the presence of pre-stressed concrete members within a structure when it is known they are present. However, if a worker notices signs that prestressed concrete is present, it is his/her responsibility to cease work immediately and inform the site supervisor of this information. Incorrect demolition procedures can cause a collapse, creating serious hazards for employees and the public. Damaged members can fail even when they are handled correctly. The possibility of a tendon and its anchorage becoming a missile should not be ignored in all forms of pre-stressed construction. Workers must follow the safe work practices in working with pre-stressed concrete as outlined by the site supervisor. Workers are not to deviate from the prescribed procedures. Additional training may be required. If a worker feels that he/she does not have the proper training or experience to safely work with pre-stressed concrete, he/she must tell the site supervisor before beginning the work. PPE may include head protection, eye protection, ear protection, respirators, hand/body protection, safety footwear, flame-proof suites, and moisture-proof boots. The site supervisor will communicate what type of PPE is required for the specific job. Environmental concerns in this type of job include dust, fumes, pollution, noise and vibration. 11.3.6 Basic Definitions and Principles


Bonded Tendons: Tendons which are substantially bonded to the concrete throughout their entire length. Pre-tensioned tendons are usually bonded. Post-tensioned tendons that are in the ducts and are grouted after stressed are considered ,,bonded. Camber: The upward deflection of the member due to process. Creep: The plastic change in volume of concrete under sustained stress. It is most marked during the early stages of the life of a concrete member. An old rule of thumb says, "One-third in three days, the second third in three months, and the last one-third in ten years." The higher the sustained stress, the greater the creep. If stress is applied at an early age, the creep will be greater. Elevated temperatures increase creep. Creep is essentially irreversible: when the stress is removed, the creep stops but does not reverse to any appreciable extent. Elastic Shortening: The change in dimensions occurring in the concrete as the precompression is applied to it during pre-stressing. External Tendons: Tendons which lie outside the cross section of the concrete body or member as cast. They may be within the void of a box girder. Concrete or grout may later bond them to it. External tendons may be in grooves or channels at the side of the concrete member or may be located inside the open box of a box girder. Internal Tendons: Tendons which are embedded within the cross section of the concrete body of member. They may be either pre-tensioned or post-tensioned tendons. Usually this refers to post-tensioned tendons located in ducts cast in the concrete. Partial Pre-stress: A design in which the degree of pre-stress is tailored to the service conditions rather than the ultimate loads. The aim usually is to provide a residual compression (zero tension) under normal service loads, but also to permit tension and even a minor degree of cracking under occasional overloads. Post-Tensioning: The imposition of pre-stress by stressing and anchoring tendons against already hardened concrete. Post-tensioning is the most commonly applied to cast-in-place concrete members, and to those requiring a curved profile of the prestressing force. Bridges, large girders, floor slabs, roofs, shells, pavements, and pressure vessels are among the constructions usually pre-stressed by post-tensioning. Post-tensioning is extremely versatile and quite free from limitations. Pre-stressing: The imposition of a state of stress on a structural body, prior to its being placed in service. Pre-stressing will enable the structural body to better withstand the forces added loads impose and to better perform its design functions. Pre-stress requires a pre-strain. It is important to remember that pre-stress cannot be imparted into a member unless that member is able to shorten. A beam may be pre-stressed by precompressing its lower flange, so that it can resist positive moment tensile stresses without cracking. A pile may be pre-stressed (pre-compressed) to maintain itself crackfree under shrinkage, transportation, handling, and driving stresses. A column may be


pre-stressed (pre-compressed) to enable it to act as an un-cracked homogeneous section of a long-column and to prevent buckling under accidental or intentional eccentric loading. A pressure vessel may be pre-stressed to resist the membrane tensile stresses due to thermal ingredients and internal pressure. A thin floor slab may be pre-stressed to remain truly flat under normal loads. Pre-tensioning: The imposition of pre-stress by stressing the tendons against external reactions before the hardening of the fresh concrete. After the concrete sets and gains a substantial portion of its ultimate strength, the tendons are released and the stress is transferred into the concrete. Pre-tensioning is most commonly applied to pre-cast concrete elements manufactured in a factory or plant. Typical products produced by pre-tensioning are roof slabs, floor slabs, piles, poles, bridge girders, wall panels, and railroad ties. A limited amount of pre-tensioning has been applied to cast-in-place concrete in the form of pavements and floor slabs. Shrinkage: A volume change of the concrete due to chemical reaction and the dryingout of the contained water. Some shrinkage occurs at set, but the largest amount occurs during drying. Shrinkage is reversible and sustained humidity or soaking will cause a swelling, largely offsetting the drying shrinkage. The effect of shrinkage is due to reducing the pre-compression in the concrete. Before the application of pre-stress, shrinkage may produce tensile cracking in the concrete which, although closing again under pre-stress, may still reduce the inherent tensile strength of the concrete and its ability to remain crack-free under load. Stage Stressing: The application of the prostrating force in a sequence of two or more steps. This is done to avoid overstressing or cracking the concrete during the construction phase, before further dead load is applied. Stress-relaxation: an irreversible plastic flow in the steel under sustained high stress. Stress-relaxation, as the name implies, leads to a reduction in the degree of stress in a tendon, thus reducing the pre-stress in the concrete. While the greatest portion occurs during a short time of very high stress, relaxation may continue for very long periods. Since it is a molecular phenomenon, various treatments of the steel can be used to reduce the stress-relaxation. Tendons: The stretched elements which are used to impart pre-compression to the concrete. Tendons may be high-strength steel wire, strands made of high-strength steel wire, high-strength alloy steel bars, or other special materials. Un-bonded Tendons: Tendons whose force is applied to the concrete member only at the anchorage. The bond throughout the length is intentionally prevented. When the post-tensioned tendon is in a duct, the duct may be filled with grease. Some posttensioned tendons are coated with corrosion-inhibiting grease and then encased in plastic. They are then placed in the forms, the concrete is poured and cured and the tendons are stretched. Single strands, so encased, are increasingly used for the prestressing of floor slabs.



A Abrasive Blade, power tool Aerial Lifts Air Compressors Asbestos Disposal Government Regulations Health Effects Medical Surveillance Monitoring Worker Exposure Notification of Workers PEL Planning Preventing Airborne Fibers Protective Practices Recordkeeping Respirator Use Safe Handling TWA Atmospheres Asphyxiating Flammable Irritant (corrosive) Toxic Attachments Axes B Basements Blasting Fire Precautions Safe Procedures Use of Explosives C 76 16-17 76 45-52 52 46 46 52 50 49 51 47 48 49 51 50 45 51 83-86 85-86 83 85 84 35 72 35 78-81 79-80 78 80


Chainsaws Chisels Chimney Demolition Clamshell Bucket Cleaning, confined spaces Clothing Asbestos Confined Spaces Confined Spaces Asphyxiating Atmospheres Cleaning Clothing Communication Problems Entry and Exit Flammable Atmospheres Irritant (corrosive) Atmospheres Monitoring Noise Permit System Physical Hazards Posting PPE Purging Rescue Plan Safety Temperature Testing Toxic Atmospheres Training Ventilating Vibration Cranes Assembly Features Hydraulics Set Up Crowbar Cutters

76 73 92-94 41-42 90-91 20 49-50 91-92 83-92 85 90-91 91 86 86 83 85 89 87 88 87 92 91 90 88 82, 85, 88 86 89 84 91 90 87 37 39 37 39 39 74 72


D Debris Removal Demolition Complete Selective Stockpiling Demolition Agents, non-explosive Demolition Ball Demolition, pre-stressed concrete E Ear Protection Electric, power tools Electrical Hazards Engineering Survey Eye Protection Equipment, Inspection Maintenance Explosives Firing Inspection after blast Exposure, asbestos Lead F Face Protection Fall Protection Files Fire, prevention and protection precautions with blasting First Aid Floor Openings Foot Protection Footcandle G Gasoline, power tools

27-28 27-28 28 28 35 81 41 94 23 75 42 8 22-23 30-32 32 80 80 81 50 59

22-23 24 73 10-11 79-80 10 28 21 14 75


Guarding, roof perimeters H Hammers Hand Protection Hand Tools Axes Chisels Crowbar Cutters Files General Safety Hammers Knives Nail Puller Power Tools Abrasive Blade Air Compressors Chainsaws Electric Gasoline Pneumatic Safety Strategies Screwdrivers Shovels Sledges Hauling Head Protection Hearing Protection I J K Knives L Ladders Lateral Shoring

25-26 73 21 72-77 72-73 73 74 72 73 71 73 72 73 74 76 76-77 76 75 75 75 71 74 74 73 36 22 23

72 14-15 17-18


Lead Avoiding Overexposure Exposure Monitoring and Assessment Government Regulations Health Effects Hygiene Practices and Facilities Methods of Compliance Administrative Controls Engineering Controls PPE Work Practice Controls MSDS OSHA Exposure Limits Planning Respirators Uses Warning Signs Lifts (aerial) Lighting Load Charts Loaders Loading, transport machinery trucks M Machinery, Transport Medical Services Medical Surveillance, asbestos Monitoring, worker exposure (asbestos) MSDS (lead) N Nail Puller Noise, confined spaces Non-explosive Demolition Agents Notification (asbestos) O

57-63 57 59 59 58 63 61 62 61 62 61 63 59 59 60, 62 57 63 16-17 13 37 34-35 34 34 33 10 52 50 63 73 87 81 49


Operator Safety P PCBs Government Regulations Health Effects Planning Prevention Protective Practices Safe Handling PEL, asbestos Permit System, confined spaces Personal Protective Equipment (PPE) Clothing Confined Spaces Eye Face Fall Prevention and Protection Foot Hand Head Hearing PFAS Respiratory Temperature PFAS Pneumatic, power tools Pre-stressed Concrete Categories Definitions Demolition Hazards Monolithic Structures Pre-Case Units Pre-Tensioned Members Progressively Pre-Stressed Structures Procedures Recognition Site Safety

40 52-57 53 53 53 55 56 52 51 88 19-26, 60 20 91 22-23 22-23 24 21 21 22 23 24-25 24 20 24 74 94-101 96 99-101 94 96 98 98 97 98 97 94 98


Purging, confined space Q R Rescue Plan, confined spaces Respiratory Protection Asbestos Lead S Safety Strategies Securing Scaffolding Screwdrivers Shoring (vertical and lateral) Shovels Sledges Signalman Signs Lead Stress (temperature) T Temperature, confined spaces Temperature Stress Torch Cutting Leak Test Safe Use Set-Up Procedures Shut-Down Procedures Transport, Machinery Trucks Dumping Hauling Loading TWA, asbestos U Utility (location)


88 24 50 60, 62 71 34 16 74 17 74 73 40 13 63 20 86 20 65-69 68 66-67 68 69 33 35 36-37 36 35-36 51 9


V Ventilation, confined spaces Vertical Shoring Vibration, confined spaces W Welding X Y Z

90 17 87 66-69



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